C programming code for Ubuntu Linux

#include <stdio.h>
 
int main() {
  system("shutdown -P now");
  return 0;
} 

C programming code for Windows 7

#include <stdio.h>
#include <stdlib.h>
 
main()
{
   char ch;
 
   printf("Do you want to shutdown your computer now (y/n)\n");
   scanf("%c",&ch);
 
   if (ch == 'y' || ch == 'Y')
      system("C:\\WINDOWS\\System32\\shutdown /s");
 
   return 0;
}

C program to shutdown or turn off computer

C Program to shutdown your computer: This program turn off i.e shutdown your computer system. Firstly it will asks you to shutdown your computer if you press 'y' the your computer will shutdown in 30 seconds, system function of "stdlib.h" is used to run an executable file shutdown.exe which is present in C:\WINDOWS\system32 in Windows XP. You can use various options while executing shutdown.exe for example -s option shutdown the computer after 30 seconds, if you wish to shutdown immediately then you can write "shutdown -s -t 0" as an argument to system function. If you wish to restart your computer then you can write "shutdown -r".

If you are using Turbo C Compiler then execute your file from folder. Press F9 to build your executable file from source program. When you run from within the compiler by pressing Ctrl+F9 it may not work.

C programming code for Windows XP

#include <stdio.h>
#include <stdlib.h>
 
main()
{
   char ch;
 
   printf("Do you want to shutdown your computer now (y/n)\n");
   scanf("%c",&ch);
 
   if (ch == 'y' || ch == 'Y')
      system("C:\\WINDOWS\\System32\\shutdown -s");
 
   return 0;
}

c program to get ip address

This c program prints ip (internet protocol) address of your computer, system function is used to execute the command ipconfig which prints ip address, subnet mask and default gateway. The code given below works for Windows xp and Windows 7. If you are using turbo c compiler then execute program from folder, it may not work when you are working in compiler and press Ctrl+F9 to run your program.

C programming code

#include<stdlib.h>
 
main()
{
   system("C:\\Windows\\System32\\ipconfig");
   system("pause");
 
   return 0;
}

c program to print date

This c program prints current system date. To print date we will use getdate function.

C programming code

#include<stdio.h>
#include<conio.h>
#include<dos.h>
 
main()
{
   struct date d;
 
   getdate(&d);
 
   printf("Current system date is %d/%d/%d",d.da_day,d.da_mon,d.da_year);
   getch();
   return 0;
}

c program to add two complex numbers

c program to add two complex numbers :- This program calculate the sum of two complex numbers which will be entered by the user and then prints it. User will have to enter the real and imaginary parts of two complex numbers. In our program we will add real parts and imaginary parts of complex numbers and prints the complex number, i is the symbol used for iota. For example if user entered two complex numbers as (1 + 2i) and (4 + 6 i) then output of program will be (5+8i). A structure is used to store complex number.

C programming code

#include <stdio.h>
 
struct complex
{
   int real, img;
};
 
main()
{
   struct complex a, b, c;
 
   printf("Enter a and b where a + ib is the first complex number.\n");
   printf("a = ");
   scanf("%d", &a.real);
   printf("b = ");
   scanf("%d", &a.img);
   printf("Enter c and d where c + id is the second complex number.\n");
   printf("c = ");
   scanf("%d", &b.real);
   printf("d = ");
   scanf("%d", &b.img);
 
   c.real = a.real + b.real;
   c.img = a.img + b.img;
 
   if ( c.img >= 0 )
      printf("Sum of two complex numbers = %d + %di\n",c.real,c.img);
   else
      printf("Sum of two complex numbers = %d %di\n",c.real,c.img);
 
   return 0;
}

C programming code using random function(Turbo C compiler only)

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
 
main()
{
   int n, max, num, c;
 
   printf("Enter the number of random numbers you want ");
   scanf("%d",&n);
 
   printf("Enter the maximum value of random number ");
   scanf("%d",&max);
 
   printf("%d random numbers from 0 to %d are :-\n",n,max);
   randomize();
 
   for ( c = 1 ; c <= n ; c++ )
   {
      num = random(max);
      printf("%d\n",num);
 
   }
 
   getch();
   return 0;
}

c program to generate random numbers

This c program generates random numbers using random function, randomize function is used to initialize random number generator. If you don't use randomize function then you will get same random numbers each time you run the program.

C programming code using rand

#include <stdio.h>
#include <stdlib.h>
 
int main() {
  int c, n;
 
  printf("Ten random numbers in [1,100]\n");
 
  for (c = 1; c <= 10; c++) {
    n = rand()%100 + 1;
    printf("%d\n", n);
  }
 
  return 0;
}

c program to delete a file

This c program deletes a file which is entered by the user, the file to be deleted should be present in the directory in which the executable file of this program is present. Extension of the file should also be entered, also note that deleted file doesn't go to recycle bin, remove macro is used to delete the file. If there is an error in deleting the file then an error will be displayed using perror function.

C programming code

#include<stdio.h>
 
main()
{
   int status;
   char file_name[25];
 
   printf("Enter the name of file you wish to delete\n");
   gets(file_name);
 
   status = remove(file_name);
 
   if( status == 0 )
      printf("%s file deleted successfully.\n",file_name);
   else
   {
      printf("Unable to delete the file\n");
      perror("Error");
   }
 
   return 0;
}

c program to list files in directory

This program list all files present in a directory/folder in which this executable file is present. For example if this executable file is present in C:\\TC\\BIN then it will lists all the files present in C:\\TC\\BIN.

C programming code

#include<stdio.h>
#include<conio.h>
#include<dir.h>
 
main()
{
   int done;
   struct ffblk a;
 
   printf("Press any key to view the files in the current directory\n");
 
   getch();
 
   done = findfirst("*.*",&a,0);
 
   while(!done)
   {
      printf("%s\n",a.ff_name);
      done = findnext(&a);
   }
 
   getch();
   return 0;
}

c program to merge two files

This c program merges two files and store their contents in an another file. The files which are to be merged are opened in read mode and the file which contains content of both the files is opened in write mode. To merge two files first we open a file and read it character by character and store the read contents in another file then we read the contents of another file and store it in file, we read two files until EOF ( end of file ) is reached.

C programming code

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
 
main()
{
   FILE *fs1, *fs2, *ft;
 
   char ch, file1[20], file2[20], file3[20];
 
   printf("Enter name of first file ");
   gets(file1);
 
   printf("Enter name of second file ");
   gets(file2);
 
   printf("Enter name of file which will store contents of two files ");
   gets(file3);
 
   fs1 = fopen(file1,"r");
   fs2 = fopen(file2,"r");
 
   if( fs1 == NULL || fs2 == NULL )
   {
      perror("Error ");
      printf("Press any key to exit...\n");
      getch();
      exit(EXIT_FAILURE);
   }
 
   ft = fopen(file3,"w");
 
   if( ft == NULL )
   {
      perror("Error ");
      printf("Press any key to exit...\n");
      exit(EXIT_FAILURE);
   }
 
   while( ( ch = fgetc(fs1) ) != EOF )
      fputc(ch,ft);
 
   while( ( ch = fgetc(fs2) ) != EOF )
      fputc(ch,ft);
 
   printf("Two files were merged into %s file successfully.\n",file3);
 
   fclose(fs1);
   fclose(fs2);
   fclose(ft);
 
   getch();
   return 0;
}

program to copy files

C program to copy files: This program copies a file, firstly you will specify the file to copy and then you will enter the name of target file, You will have to mention the extension of file also. We will open the file that we wish to copy in read mode and target file in write mode.

C programming code

#include <stdio.h>
#include <stdlib.h>
 
main()
{
   char ch, source_file[20], target_file[20];
   FILE *source, *target;
 
   printf("Enter name of file to copy\n");
   gets(source_file);
 
   source = fopen(source_file, "r");
 
   if( source == NULL )
   {
      printf("Press any key to exit...\n");
      exit(EXIT_FAILURE);
   }
 
   printf("Enter name of target file\n");
   gets(target_file);
 
   target = fopen(target_file, "w");
 
   if( target == NULL )
   {
      fclose(source);
      printf("Press any key to exit...\n");
      exit(EXIT_FAILURE);
   }
 
   while( ( ch = fgetc(source) ) != EOF )
      fputc(ch, target);
 
   printf("File copied successfully.\n");
 
   fclose(source);
   fclose(target);
 
   return 0;
}

c program to read a file

C program to read a file :- This program reads a file entered by the user and displays it's contents on the screen, fopen function is used to open a file, it returns a pointer to structure FILE. FILE is a predefined structure in stdio.h . If the file is successfully opened then fopen returns a pointer to file and if it is unable to open a file then it returns NULL. fgetc function returns a character which is read from the file and fclose function closes the file. Opening a file means we bring file from disk to ram to perform operations on it. The file must be present in the directory in which the executable file of this code sis present.

C program to open a file

C programming code to open a file and to print it contents on screen.

#include<stdio.h>
#include<stdlib.h>
 
main()
{
   char ch, file_name[25];
   FILE *fp;
 
   printf("Enter the name of file you wish to see ");
   gets(file_name);
 
   fp = fopen(file_name,"r"); // read mode
 
   if( fp == NULL )
   {
      perror("Error while opening the file.\n");
      exit(EXIT_FAILURE);
   }
 
   printf("The contents of %s file are :- \n\n", file_name);
 
   while( ( ch = fgetc(fp) ) != EOF )
      printf("%c",ch);
 
   fclose(fp);
   return 0;
}

String concatenation without strcat

#include<stdio.h>
 
void concatenate_string(char*, char*);
 
main()
{
    char original[100], add[100];
 
    printf("Enter source string\n");
    gets(original);
 
    printf("Enter string to concatenate\n");
    gets(add);
 
    concatenate_string(original, add);
 
    printf("String after concatenation is \"%s\"\n", original);
 
    return 0;
}
 
void concatenate_string(char *original, char *add)
{
   while(*original)
      original++;
 
   while(*add)
   {
      *original = *add;
      add++;
      original++;
   }
   *original = '\0';
}

c program to concatenate strings

This program concatenates strings, for example if the first string is "c " and second string is "program" then on concatenating these two strings we get the string "c program". To concatenate two strings we use strcat function of string.h, to concatenate without using library function see another code below which uses pointers.

C code

#include<stdio.h>
#include<conio.h>
#include<string.h>
 
main()
{
   char a[100], b[100];
 
   printf("Enter the first string\n");
   gets(a);
 
   printf("Enter the second string\n");
   gets(b);
 
   strcat(a,b);
 
   printf("String obtained on concatenation is %s\n",a);
 
   getch();
   return 0;
}

Change string to lower case without strlwr

#include<stdio.h>
 
void lower_string(char*);
 
main()
{
   char string[100];
 
   printf("Enter a string to convert it into lower case\n");
   gets(string);
 
   lower_string(string);
 
   printf("Entered string in lower case is \"%s\"\n", string);
 
   return 0;
}
 
void lower_string(char *string)
{
   while(*string)
   {
      if ( *string >= 'A' && *string <= 'Z' )
      {
         *string = *string + 32;
      }
      string++;
   }
}

Change string to upper case without strupr

#include<stdio.h>
 
void upper_string(char*);
 
main()
{
   char string[100];
 
   printf("Enter a string to convert it into upper case\n");
   gets(string);
 
   upper_string(string);
 
   printf("Entered string in upper case is \"%s\"\n", string);
 
   return 0;
}
 
void upper_string(char *string)
{
   while(*string)
   {
       if ( *string >= 'a' && *string <= 'z' )
       {
          *string = *string - 32;
       }
       string++;
   }
}

strupr in c

#include<stdio.h>
#include<string.h>
 
main()
{
    char string[] = "strupr in c";
 
    printf("%s\n",strupr(string));
 
    return  0;
}

strlwr, strupr in c

Here we will change string case with and without strlwr, strupr functions.

strlwr in c

#include<stdio.h>
#include<string.h>
 
main()
{
    char string[] = "Strlwr in C";
 
    printf("%s\n",strlwr(string));
 
    return  0;
}

c program to copy a string using pointers

: here we copy string without using strcmp by creating our own function which uses pointers.

#include<stdio.h>
 
void copy_string(char*, char*);
 
main()
{
    char source[100], target[100];
 
    printf("Enter source string\n");
    gets(source);
 
    copy_string(target, source);
 
    printf("Target string is \"%s\"\n", target);
 
    return 0;
}
 
void copy_string(char *target, char *source)
{
   while(*source)
   {
      *target = *source;
      source++;
      target++;
   }
   *target = '\0';
}

string copying in c programming

This program copy string using library function strcpy, to copy string without using strcpy see source code below in which we have made our own function to copy string.

C program to copy a string

#include<stdio.h>
#include<string.h>
 
main()
{
   char source[] = "C program";
   char destination[50];
 
   strcpy(destination, source);
 
   printf("Source string: %s\n", source);
   printf("Destination string: %s\n", destination);
 
   return 0;
}

c program to sort a string in alphabetic order

C program to sort a string in alphabetic order: For example if user will enter a string "programming" then output will be "aggimmnoprr" or output string will contain characters in alphabetical order.

C programming code

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
void sort_string(char*);
 
main()
{
   char string[100];
 
   printf("Enter some text\n");
   gets(string);
 
   sort_string(string);
   printf("%s\n", string);
 
   return 0;
}
 
void sort_string(char *s)
{
   int c, d = 0, length;
   char *pointer, *result, ch;
 
   length = strlen(s);
 
   result = (char*)malloc(length+1);
 
   pointer = s;
 
   for ( ch = 'a' ; ch <= 'z' ; ch++ )
   {
      for ( c = 0 ; c < length ; c++ )
      {
         if ( *pointer == ch )
         {
            *(result+d) = *pointer;
            d++;
         }
         pointer++;
      }
      pointer = s;
   }
   *(result+d) = '\0';
 
   strcpy(s, result);
   free(result);
}

C code for all substrings of a string

#include <stdio.h>
#include <string.h>
#include <malloc.h>
 
char* substring(char*, int, int);
 
main() 
{
   char string[100], *pointer;
   int position = 1, length = 1, temp, string_length;
 
   printf("Enter a string\n");
   gets(string);
 
   temp = string_length = strlen(string);
 
   printf("Substring of \"%s\" are\n", string);
 
   while (position <= string_length)
   {
      while (length <= temp)
      {
         pointer = substring(string, position, length);
         printf("%s\n", pointer);
         free(pointer);
         length++;
      }
      temp--;
      position++;
      length = 1;
   }
 
   return 0;
}
 
/* Use substring function given in above c program*/ 

Substring in c programming, c substring

Substring in c programming: c programming code to find a substring from a given string and for all substrings of a string, For example substrings of string "the" are "t", "th", "the", "h", "he" and "e" to find substring we create our own c substring function which returns a pointer to string. String address, length of substring required and position from where to extract substring are the three arguments passed to function. String.h does not contain any library function to directly find substring.

C substring code

#include <stdio.h>
#include <malloc.h>
 
char* substring(char*, int, int);
 
main() 
{
   char string[100], *pointer;
   int position, length;
 
   printf("Enter a string\n");
   gets(string);
 
   printf("Enter the position and length of substring\n");
   scanf("%d%d",&position, &length);
 
   pointer = substring( string, position, length);
 
   printf("Required substring is \"%s\"\n", pointer);
 
   free(pointer);
 
   return 0;
}
 
/*C substring function: It returns a pointer to the substring */
 
char *substring(char *string, int position, int length) 
{
   char *pointer;
   int c;
 
   pointer = malloc(length+1);
 
   if (pointer == NULL)
   {
      printf("Unable to allocate memory.\n");
      exit(EXIT_FAILURE);
   }
 
   for (c = 0 ; c < position -1 ; c++) 
      string++; 
 
   for (c = 0 ; c < length ; c++)
   {
      *(pointer+c) = *string;      
      string++;   
   }
 
   *(pointer+c) = '\0';
 
   return pointer;
}

C programming code using pointers

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define TRUE 1
#define FALSE 0
 
int check_vowel(char);
 
main()
{
   char string[100], *temp, *pointer, ch, *start;
 
   printf("Enter a string\n");
   gets(string);
 
   temp = string;
   pointer = (char*)malloc(100);
 
  if( pointer == NULL )
   {
      printf("Unable to allocate memory.\n");
      exit(EXIT_FAILURE);
   }
 
   start = pointer;
 
   while(*temp)
   {
      ch = *temp;
 
      if ( !check_vowel(ch) )
      {
         *pointer = ch;
         pointer++;
      }
      temp++;
   }
   *pointer = '\0';
 
   pointer = start;
   strcpy(string, pointer); /* If you wish to convert original string */
   free(pointer);
 
   printf("String after removing vowel is \"%s\"\n", string);
 
   return 0;
}
 
int check_vowel(char a)
{
   if ( a >= 'A' && a <= 'Z' )
      a = a + 'a' - 'A';
 
   if ( a == 'a' || a == 'e' || a == 'i' || a == 'o' || a == 'u')
      return TRUE;
 
   return FALSE;
}

remove vowels string c

Remove vowels string c: c program to remove or delete vowels from a string, if the input string is "c programming" then output will be "c prgrmmng". In the program we create a new string and process entered string character by character, and if a vowel is found it is not added to new string otherwise the character is added to new string, after the string ends we copy the new string into original string. Finally we obtain a string without any vowels.

C programming code

#include <stdio.h>
#include <string.h>
 
int check_vowel(char);
 
int main()
{
  char s[100], t[100];
  int i, j = 0;
 
  printf("Enter a string to delete vowels\n");
  gets(s);
 
  for(i = 0; s[i] != '\0'; i++) {
    if(check_vowel(s[i]) == 0) {       //not a vowel
      t[j] = s[i];
      j++;
    }
  }
 
  t[j] = '\0';
 
  strcpy(s, t);    //We are changing initial string
 
  printf("String after deleting vowels: %s\n", s);
 
  return 0;
}
 
 
int check_vowel(char c)
{
  switch(c) {
    case 'a':
    case 'A':
    case 'e':
    case 'E':
    case 'i':
    case 'I':
    case 'o':
    case 'O':
    case 'u':
    case 'U':
      return 1;
    default:
      return 0;
  }
}

C program check palindrome

#include <stdio.h>
 
int is_palindrome(char*);
void copy_string(char*, char*);
void reverse_string(char*);
int string_length(char*);
int compare_string(char*, char*);
 
main()
{
   char string[100];
   int result;
 
   printf("Enter a string\n");
   gets(string);
 
   result = is_palindrome(string);
 
   if ( result == 1 )
      printf("\"%s\" is a palindrome string.\n", string);
   else
      printf("\"%s\" is not a palindrome string.\n", string); 
 
   return 0;
}
 
int is_palindrome(char *string)
{
   int check, length;
   char *reverse;
 
   length = string_length(string);    
   reverse = (char*)malloc(length+1);    
 
   copy_string(reverse, string);
   reverse_string(reverse);
 
   check = compare_string(string, reverse);
 
   free(reverse);
 
   if ( check == 0 )
      return 1;
   else
      return 0;
}
 
int string_length(char *string)
{
   int length = 0;  
 
   while(*string)
   {
      length++;
      string++;
   }
 
   return length;
}
 
void copy_string(char *target, char *source)
{
   while(*source)
   {
      *target = *source;
      source++;
      target++;
   }
   *target = '\0';
}
 
void reverse_string(char *string) 
{
   int length, c;
   char *begin, *end, temp;
 
   length = string_length(string);
 
   begin = string;
   end = string;
 
   for ( c = 0 ; c < ( length - 1 ) ; c++ )
       end++;
 
   for ( c = 0 ; c < length/2 ; c++ ) 
   {        
      temp = *end;
      *end = *begin;
      *begin = temp;
 
      begin++;
      end--;
   }
}
 
int compare_string(char *first, char *second)
{
   while(*first==*second)
   {
      if ( *first == '\0' || *second == '\0' )
         break;
 
      first++;
      second++;
   }
   if( *first == '\0' && *second == '\0' )
      return 0;
   else
      return -1;
}

C program for palindrome without using string functions

#include <stdio.h>
#include <string.h>
 
main()
{
   char text[100];
   int begin, middle, end, length = 0;
 
   gets(text);
 
   while ( text[length] != '\0' )
      length++;
 
   end = length - 1;
   middle = length/2;
 
   for( begin = 0 ; begin < middle ; begin++ )
   {
      if ( text[begin] != text[end] )
      {
         printf("Not a palindrome.\n");
         break;
      }
      end--;
   }
   if( begin == middle )
      printf("Palindrome.\n");
 
   return 0;
}

Palindrome number in c

#include <stdio.h>
 
main()
{
   int n, reverse = 0, temp;
 
   printf("Enter a number to check if it is a palindrome or not\n");
   scanf("%d",&n);
 
   temp = n;
 
   while( temp != 0 )
   {
      reverse = reverse * 10;
      reverse = reverse + temp%10;
      temp = temp/10;
   }
 
   if ( n == reverse )
      printf("%d is a palindrome number.\n", n);
   else
      printf("%d is not a palindrome number.\n", n);
 
   return 0;
}

c program for palindrome

 

C program for palindrome or palindrome in c programming: palindrome program in c language, c code to check if a string is a palindrome or not and for palindrome number. This program works as follows :- at first we copy the entered string into a new string, and then we reverse the new string and then compares it with original string. If both of them have same sequence of characters i.e. they are identical then the entered string is a palindrome otherwise not. To perform copy, reverse and compare operations we use strcpy, strrev and strcmp functions of string.h respectively, if you do not wish to use these functions see c programming code for palindrome without using string functions. Some palindrome strings examples are "dad", "radar", "madam" etc.

C program for palindrome

#include <stdio.h>
#include <string.h>
 
main()
{
   char a[100], b[100];
 
   printf("Enter the string to check if it is a palindrome\n");
   gets(a);
 
   strcpy(b,a);
   strrev(b);
 
   if( strcmp(a,b) == 0 )
      printf("Entered string is a palindrome.\n");
   else
      printf("Entered string is not a palindrome.\n");
 
   return 0;
}

C program to reverse a string using recursion

#include<stdio.h>
#include<string.h>
 
void reverse(char*,int,int);
 
main()
{
   char a[100];
 
   gets(a);
 
   reverse(a, 0, strlen(a)-1);
 
   printf("%s\n",a);
 
   return 0;
}
 
void reverse(char *x, int beg, int end)
{
   char a, b, c;
 
   if ( beg >= end )
      return;   
 
   c = *(x+beg);
   *(x+beg) = *(x+end);
   *(x+end) = c;
 
   reverse(x, ++beg, --end);
}

C program to reverse a string using pointers

: Now we will invert string using pointers or without using library function strrev.

#include<stdio.h>
 
int string_length(char*);
void reverse(char*);
 
main() 
{
   char string[100];
 
   printf("Enter a string\n");
   gets(string);
 
   reverse(string);
 
   printf("Reverse of entered string is \"%s\".\n", string);
 
   return 0;
}
 
void reverse(char *string) 
{
   int length, c;
   char *begin, *end, temp;
 
   length = string_length(string);
 
   begin = string;
   end = string;
 
   for ( c = 0 ; c < ( length - 1 ) ; c++ )
      end++;
 
   for ( c = 0 ; c < length/2 ; c++ ) 
   {        
      temp = *end;
      *end = *begin;
      *begin = temp;
 
      begin++;
      end--;
   }
}
 
int string_length(char *pointer)
{
   int c = 0;
 
   while( *(pointer+c) != '\0' )
      c++;
 
   return c;
}

Reverse string

This program reverses a string entered by the user. For example if a user enters a string "reverse me" then on reversing the string will be "em esrever". We show you three different methods to reverse string the first one uses strrev library function of string.h header file and in second we make our own function to reverse string using pointers, reverse string using recursion and Reverse words in string. If you are using first method then you must include string.h in your program.

C programming code

/* String reverse in c*/

#include<stdio.h>
#include<string.h>
 
main()
{
   char arr[100];
 
   printf("Enter a string to reverse\n");
   gets(arr);
 
   strrev(arr);
 
   printf("Reverse of entered string is \n%s\n",arr);
 
   return 0;
}

sring concatenation without strcat

#include<stdio.h>
 
void concatenate_string(char*, char*);
 
main()
{
    char original[100], add[100];
 
    printf("Enter source string\n");
    gets(original);
 
    printf("Enter string to concatenate\n");
    gets(add);
 
    concatenate_string(original, add);
 
    printf("String after concatenation is \"%s\"\n", original);
 
    return 0;
}
 
void concatenate_string(char *original, char *add)
{
   while(*original)
      original++;
 
   while(*add)
   {
      *original = *add;
      add++;
      original++;
   }
   *original = '\0';
}

program to concatenate strings

This program concatenates strings, for example if the first string is "c " and second string is "program" then on concatenating these two strings we get the string "c program". To concatenate two strings we use strcat function of string.h, to concatenate without using library function see another code below which uses pointers.

C code

#include<stdio.h>
#include<conio.h>
#include<string.h>
 
main()
{
   char a[100], b[100];
 
   printf("Enter the first string\n");
   gets(a);
 
   printf("Enter the second string\n");
   gets(b);
 
   strcat(a,b);
 
   printf("String obtained on concatenation is %s\n",a);
 
   getch();
   return 0;
}

c program to copy a string using pointers

: here we copy string without using strcmp by creating our own function which uses pointers.

#include<stdio.h>
 
void copy_string(char*, char*);
 
main()
{
    char source[100], target[100];
 
    printf("Enter source string\n");
    gets(source);
 
    copy_string(target, source);
 
    printf("Target string is \"%s\"\n", target);
 
    return 0;
}
 
void copy_string(char *target, char *source)
{
   while(*source)
   {
      *target = *source;
      source++;
      target++;
   }
   *target = '\0';
}

string copying in c programming

This program copy string using library function strcpy, to copy string without using strcpy see source code below in which we have made our own function to copy string.

C program to copy a string

#include<stdio.h>
#include<string.h>
 
main()
{
   char source[] = "C program";
   char destination[50];
 
   strcpy(destination, source);
 
   printf("Source string: %s\n", source);
   printf("Destination string: %s\n", destination);
 
   return 0;
}

C program to compare two strings using pointers

In this method we will make our own function to perform string comparison, we will use character pointers in our function to manipulate string.

#include<stdio.h>
 
int compare_string(char*, char*);
 
main()
{
    char first[100], second[100], result;
 
    printf("Enter first string\n");
    gets(first);
 
    printf("Enter second string\n");
    gets(second);
 
    result = compare_string(first, second);
 
    if ( result == 0 )
       printf("Both strings are same.\n");
    else
       printf("Entered strings are not equal.\n");
 
    return 0;
}
 
int compare_string(char *first, char *second)
{
   while(*first==*second)
   {
      if ( *first == '\0' || *second == '\0' )
         break;
 
      first++;
      second++;
   }
   if( *first == '\0' && *second == '\0' )
      return 0;
   else
      return -1;
}

C program to compare two strings without using strcmp

Here we create our own function to compare strings.

int compare(char a[], char b[])
{
   int c = 0;
 
   while( a[c] == b[c] )
   {
      if( a[c] == '\0' || b[c] == '\0' )
         break;
      c++;
   }
   if( a[c] == '\0' && b[c] == '\0' )
      return 0;
   else
      return -1;
}

c program to compare two strings

This c program compares two strings using strcmp, without strcmp and using pointers. For comparing strings without using library function see another code below.

C program to compare two strings using strcmp

#include<stdio.h>
#include<string.h>
 
main()
{
   char a[100], b[100];
 
   printf("Enter the first string\n");
   gets(a);
 
   printf("Enter the second string\n");
   gets(b);
 
   if( strcmp(a,b) == 0 )
      printf("Entered strings are equal.\n");
   else
      printf("Entered strings are not equal.\n");
 
   return 0;
}

Function to find string length

Function to find string length

int string_length(char *s)
{
   int c = 0;
 
   while(*(s+c))
      c++;
 
   return c;
}

C program to find string length without strlen

C program to find length of a string using pointers.

#include<stdio.h>
 
main()
{
   char array[100], *pointer;
   int length = 0;
 
   printf("Enter a string\n");
   gets(array);
 
   pointer = array;
 
   while(*(pointer+length))
      length++;
 
   printf("Length of entered string = %d\n",length);
 
   return 0;
}

String length

This program prints length of string, for example consider the string "c programming" it's length is 13. Null character is not counted when calculating string length. To find string length we use strlen function of string.h.

C program to find string length

#include<stdio.h>
#include<string.h>
 
main()
{
   char a[100];
   int length;
 
   printf("Enter a string to calculate it's length\n");
   gets(a);
 
   length = strlen(a);
 
   printf("Length of entered string is = %d\n",length);
 
   return 0;
}

c program print string

Input string containing spaces

#include <stdio.h>
 
main()
{
   char a[80];
 
   gets(a);
 
   printf("%s\n", a);
 
   return 0;
}

c program print string

C programming code

#include <stdio.h>
 
main()
{
    char array[100];
 
    printf("Enter a string\n");
    scanf("%s", array);
 
    printf("You entered the string %s\n",array);
    return 0;
}

c program print string

This program print a string. String can be printed by using various functions such as printf, puts.

Code

#include <stdio.h>
 
main()
{
    char array[20] = "Hello World";
 
    printf("%s\n",array);
 
    return 0;
}

Multiply two matrices

coming sooon

c program to transpose a matrix

This c program prints transpose of a matrix. It is obtained by interchanging rows and columns of a matrix. For example if a matrix is
1 2
3 4
5 6
then transpose of above matrix will be
1 3 5
2 4 6
When we transpose a matrix then the order of matrix changes, but for a square matrix order remains same.

Code

#include<stdio.h>
 
main()
{
   int m, n, c, d, matrix[10][10], transpose[10][10];
 
   printf("Enter the number of rows and columns of matrix ");
   scanf("%d%d",&m,&n);
   printf("Enter the elements of matrix \n");
 
   for( c = 0 ; c < m ; c++ )
   {
      for( d = 0 ; d < n ; d++ )
      {
         scanf("%d",&matrix[c][d]);
      }
   }
 
   for( c = 0 ; c < m ; c++ )
   {
      for( d = 0 ; d < n ; d++ )
      {
         transpose[d][c] = matrix[c][d];
      }
   }
 
   printf("Transpose of entered matrix :-\n");
 
   for( c = 0 ; c < n ; c++ )
   {
      for( d = 0 ; d < m ; d++ )
      {
         printf("%d\t",transpose[c][d]);
      }  
      printf("\n");
   }
 
   return 0;
}

Subtract matrices

C code to subtract matrices of any order. This program finds difference between corresponding elements of two matrices and then print the resultant matrix.

C programming code

#include<stdio.h>
 
int main()
{
  int m, n, c, d, first[10][10], second[10][10], difference[10][10];
 
  printf("Enter the number of rows and columns of matrix\n");
  scanf("%d%d", &m, &n);
  printf("Enter the elements of first matrix\n");
 
  for (c = 0; c < m; c++)
    for (d = 0 ; d < n; d++)
      scanf("%d", &first[c][d]);
 
  printf("Enter the elements of second matrix\n");
 
  for (c = 0; c < m; c++)
    for (d = 0; d < n; d++)
        scanf("%d", &second[c][d]);
 
  for (c = 0; c < m; c++)
    for (d = 0; d < n; d++)
      difference[c][d] = first[c][d] - second[c][d];
 
  printf("difference of entered matrices:-\n");
 
  for (c = 0; c < m; c++)
  {
    for (d = 0; d < n; d++)
      printf("%d\t",difference[c][d]);
 
    printf("\n");
  }
 
  return 0;
}

c program to add two matrix

This c program add two matrices i.e. compute the sum of two matrices and then print it. Firstly user will be asked to enter the order of matrix ( number of rows and columns ) and then two matrices. For example if the user entered order as 2, 2 i.e. two rows and two columns and matrices as
First Matrix :-
1 2
3 4
Second matrix :-
4 5
-1 5
then output of the program ( sum of First and Second matrix ) will be
5 7
2 9

C programming code

#include <stdio.h>
 
main()
{
   int m, n, c, d, first[10][10], second[10][10], sum[10][10];
 
   printf("Enter the number of rows and columns of matrix ");
   scanf("%d%d", &m, &n);
   printf("Enter the elements of first matrix\n");
 
   for ( c = 0 ; c < m ; c++ )
      for ( d = 0 ; d < n ; d++ )
         scanf("%d", &first[c][d]);
 
   printf("Enter the elements of second matrix\n");
 
   for ( c = 0 ; c < m ; c++ )
      for ( d = 0 ; d < n ; d++ )
            scanf("%d", &second[c][d]);
 
   for ( c = 0 ; c < m ; c++ )
      for ( d = 0 ; d < n ; d++ )
         sum[c][d] = first[c][d] + second[c][d];
 
   printf("Sum of entered matrices:-\n");
 
   for ( c = 0 ; c < m ; c++ )
   {
      for ( d = 0 ; d < n ; d++ )
         printf("%d\t", sum[c][d]);
 
      printf("\n");
   }
 
   return 0;
}

Insertion sort

coming soon .....

Bubble sort

coming soon ....

selection sort in c

Selection sort in c: c program for selection sort to sort numbers. This code implements selection sort algorithm to arrange numbers of an array in ascending order. With a little modification it will arrange numbers in descending order.

Selection sort algorithm implementation in c

#include<stdio.h>
 
main()
{
   int array[100], n, c, d, position, swap;
 
   printf("Enter number of elements\n");
   scanf("%d", &n);
 
   printf("Enter %d integers\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d", &array[c]);
 
   for ( c = 0 ; c < ( n - 1 ) ; c++ )
   {
      position = c;
 
      for ( d = c + 1 ; d < n ; d++ )
      {
         if ( array[position] > array[d] )
            position = d;
      }
      if ( position != c )
      {
         swap = array[c];
         array[c] = array[position];
         array[position] = swap;
      }
   }
 
   printf("Sorted list in ascending order:\n");
 
   for ( c = 0 ; c < n ; c++ )
      printf("%d\n", array[c]);
 
   return 0;
}

C program to merge two arrays

C program to merge two arrays into third array: Arrays are assumed to be sorted in ascending order. You enter two short sorted arrays and combine them to get a large array.

Code to merge two sorted arrays

#include <stdio.h>
 
void merge(int [], int, int [], int, int []);
 
int main() {
  int a[100], b[100], m, n, c, sorted[200];
 
  printf("Input number of elements in first array\n");
  scanf("%d", &m);
 
  printf("Input %d integers\n", m);
  for (c = 0; c < m; c++) {
    scanf("%d", &a[c]);
  }
 
  printf("Input number of elements in second array\n");
  scanf("%d", &n);
 
  printf("Input %d integers\n", n);
  for (c = 0; c < n; c++) {
    scanf("%d", &b[c]);
  }
 
  merge(a, m, b, n, sorted);
 
  printf("Sorted array:\n");
 
  for (c = 0; c < m + n; c++) {
    printf("%d\n", sorted[c]);
  }
 
  return 0;
}
 
void merge(int a[], int m, int b[], int n, int sorted[]) {
  int i, j, k;
 
  j = k = 0;
 
  for (i = 0; i < m + n;) {
    if (j < m && k < n) {
      if (a[j] < b[k]) {
        sorted[i] = a[j];
        j++;
      }
      else {
        sorted[i] = b[k];
        k++;
      }
      i++;
    }
    else if (j == m) {
      for (; i < m + n;) {
        sorted[i] = b[k];
        k++;
        i++;
      }
    }
    else {
      for (; i < m + n;) {
        sorted[i] = a[j];
        j++;
        i++;
      }
    }
  }
}

c program to delete an element from an array

This program delete an element from an array. Deleting an element does not affect the size of array. It is also checked whether deletion is possible or not, For example if array is containing five elements and you want to delete element at position six which is not possible.

code

#include <stdio.h>
 
main()
{
   int array[100], position, c, n;
 
   printf("Enter number of elements in array\n");
   scanf("%d", &n);
 
   printf("Enter %d elements\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d", &array[c]);
 
   printf("Enter the location where you wish to delete element\n");
   scanf("%d", &position);
 
   if ( position >= n+1 )
      printf("Deletion not possible.\n");
   else
   {
      for ( c = position - 1 ; c < n - 1 ; c++ )
         array[c] = array[c+1];
 
      printf("Resultant array is\n");
 
      for( c = 0 ; c < n - 1 ; c++ )
         printf("%d\n", array[c]);
   }
 
   return 0;
}

c program to insert an element in an array

This code will insert an element into an array, For example consider an array a[10] having three elements in it initially and a[0] = 1, a[1] = 2 and a[2] = 3 and you want to insert a number 45 at location 1 i.e. a[0] = 45, so we have to move elements one step below so after insertion a[1] = 1 which was a[0] initially, and a[2] = 2 and a[3] = 3. Array insertion does not mean increasing its size i.e array will not be containing 11 elements.

Code

#include <stdio.h>
 
int main()
{
   int array[100], position, c, n, value;
 
   printf("Enter number of elements in array\n");
   scanf("%d", &n);
 
   printf("Enter %d elements\n", n);
 
   for (c = 0; c < n; c++)
      scanf("%d", &array[c]);
 
   printf("Enter the location where you wish to insert an element\n");
   scanf("%d", &position);
 
   printf("Enter the value to insert\n");
   scanf("%d", &value);
 
   for (c = n - 1; c >= position - 1; c--)
      array[c+1] = array[c];
 
   array[position-1] = value;
 
   printf("Resultant array is\n");
 
   for (c = 0; c <= n; c++)
      printf("%d\n", array[c]);
 
   return 0;
}

c program to reverse an array using pointers

#include<stdio.h>
#include<stdlib.h>
 
void reverse_array(int*, int);
 
main()
{
   int n, c, *pointer;
 
   scanf("%d",&n);
 
   pointer = (int*)malloc(sizeof(int)*n);
 
   if( pointer == NULL )
      exit(EXIT_FAILURE);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d",(pointer+c));
 
   reverse_array(pointer, n);
 
   printf("Original array on reversal is\n");
 
   for ( c = 0 ; c < n ; c++ )
      printf("%d\n",*(pointer+c));
 
   free(pointer);
 
   return 0;
}
 
void reverse_array(int *pointer, int n)
{
   int *s, c, d;
 
   s = (int*)malloc(sizeof(int)*n);
 
   if( s == NULL )
      exit(EXIT_FAILURE);
 
   for ( c = n - 1, d = 0 ; c >= 0 ; c--, d++ )
      *(s+d) = *(pointer+c);
 
   for ( c = 0 ; c < n ; c++ )
      *(pointer+c) = *(s+c);
 
   free(s);
}

Reverse array by swapping(without using additional memory)

#include <stdio.h>
 
int main() {
  int array[100], n, c, t, end;
 
  scanf("%d", &n);
  end = n - 1;
 
  for (c = 0; c < n; c++) {
    scanf("%d", &array[c]);
  }
 
  for (c = 0; c < n/2; c++) {
    t          = array[c];
    array[c]   = array[end];
    array[end] = t;
 
    end--;
  }
 
  printf("Reversed array elements are:\n");
 
  for (c = 0; c < n; c++) {
    printf("%d\n", array[c]);
  }
 
  return 0;
}

c program to reverse an array

c program to reverse an array :- This program reverses the array elements. For example if a is an array of integers with three elements
such that
a[0] = 1
a[1] = 2
a[2] = 3
then on reversing the array will be
a[0] = 3
a[1] = 2
a[0] = 1

Given below is the c code to reverse an array .

C programming code

#include <stdio.h>
 
int main()
{
   int n, c, d, a[100], b[100];
 
   printf("Enter the number of elements in array\n");
   scanf("%d", &n);
 
   printf("Enter the array elements\n");
 
   for (c = 0; c < n ; c++)
      scanf("%d", &a[c]);
 
   /*
    * Copying elements into array b starting from end of array a
    */
 
   for (c = n - 1, d = 0; c >= 0; c--, d++)
      b[d] = a[c];
 
   /*
    * Copying reversed array into original.
    * Here we are modifying original array, this is optional.
    */
 
   for (c = 0; c < n; c++)
      a[c] = b[c];
 
   printf("Reverse array is\n");
 
   for (c = 0; c < n; c++)
      printf("%d\n", a[c]);
 
   return 0;
}

C program for binary search

C program for binary search: This code implements binary search in c language. It can only be used for sorted arrays, but it's fast as compared to linear search. If you wish to use binary search on an array which is not sorted then you must sort it using some sorting technique say merge sort and then use binary search algorithm to find the desired element in the list. If the element to be searched is found then its position is printed.

The code below assumes that the input numbers are in ascending order.

Code

#include<stdio.h>
 
main()
{
   int c, first, last, middle, n, search, array[100];
 
   printf("Enter number of elements\n");
   scanf("%d",&n);
 
   printf("Enter %d integers\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d",&array[c]);
 
   printf("Enter value to find\n");
   scanf("%d",&search);
 
   first = 0;
   last = n - 1;
   middle = (first+last)/2;
 
   while( first <= last )
   {
      if ( array[middle] < search )
         first = middle + 1;    
      else if ( array[middle] == search ) 
      {
         printf("%d found at location %d.\n", search, middle+1);
         break;
      }
      else
         last = middle - 1;
 
      middle = (first + last)/2;
   }
   if ( first > last )
      printf("Not found! %d is not present in the list.\n", search);
 
   return 0;   
}

C program for linear search using function

#include<stdio.h>
 
int linear_search(int*, int, int);
 
main()
{
   int array[100], search, c, n, position;
 
   printf("Enter the number of elements in array\n");
   scanf("%d",&n);
 
   printf("Enter %d numbers\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d",&array[c]);
 
   printf("Enter the number to search\n");
   scanf("%d",&search);
 
   position = linear_search(array, n, search);
 
   if ( position == -1 )
      printf("%d is not present in array.\n", search);
   else
      printf("%d is present at location %d.\n", search, position+1);
 
   return 0;
} 
 
int linear_search(int *pointer, int n, int find)
{
   int c;
 
   for ( c = 0 ; c < n ; c++ )
   {
      if ( *(pointer+c) == find )
         return c;
   }
 
   return -1;
}

Linear search for multiple occurrences

In the code below we will print all the locations at which required element is found and also the number of times it occur in the list.

#include<stdio.h>
 
main()
{
   int array[100], search, c, n, count = 0;
 
   printf("Enter the number of elements in array\n");
   scanf("%d",&n);
 
   printf("Enter %d numbers\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d",&array[c]);
 
   printf("Enter the number to search\n");
   scanf("%d",&search);
 
   for ( c = 0 ; c < n ; c++ )
   {
      if ( array[c] == search )    
      {
         printf("%d is present at location %d.\n", search, c+1);
  count++;
      }
   }
   if ( count == 0 )
      printf("%d is not present in array.\n", search);
   else
      printf("%d is present %d times in array.\n", search, count);
 
   return 0;
}

linear search in c

Linear search in c programming: The following code implements linear search ( Searching algorithm ) which is used to find whether a given number is present in an array and if it is present then at what location it occurs.It is also known as sequential search. It is very simple and works as follows: We keep on comparing each element with the element to search until the desired element is found or list ends. Linear search in c language for multiple occurrences and using function.

Linear search c program

#include<stdio.h>
 
main()
{
   int array[100], search, c, number;
 
   printf("Enter the number of elements in array\n");
   scanf("%d",&number);
 
   printf("Enter %d numbers\n", number);
 
   for ( c = 0 ; c < number ; c++ )
      scanf("%d",&array[c]);
 
   printf("Enter the number to search\n");
   scanf("%d",&search);
 
   for ( c = 0 ; c < number ; c++ )
   {
      if ( array[c] == search )     /* if required element found */
      {
         printf("%d is present at location %d.\n", search, c+1);
  break;
      }
   }
   if ( c == number )
      printf("%d is not present in array.\n", search);     
 
   return 0;
}

c program to find minimum element in array : using pointers

#include <stdio.h>
 
main() 
{
    int array[100], *minimum, size, c, location = 1;
 
    printf("Enter the number of elements in array\n");
    scanf("%d",&size);
 
    printf("Enter %d integers\n", size);
 
    for ( c = 0 ; c < size ; c++ )
        scanf("%d", &array[c]);
 
    minimum = array;
    *minimum = *array;
 
    for ( c = 1 ; c < size ; c++ ) 
    {
        if ( *(array+c) < *minimum ) 
        {
           *minimum = *(array+c);
           location = c+1;
        }
    } 
 
    printf("Minimum element is present at location number %d and it's value is %d.\n", location, *minimum);
    return 0;
}

c program to find minimum element in array

C code to find minimum or smallest element present in an array. It also prints the location or index at which minimum element occurs in array. This can also be done by using pointers (see both the codes).

C programming code

#include <stdio.h>
 
main() 
{
    int array[100], minimum, size, c, location = 1;
 
    printf("Enter the number of elements in array\n");
    scanf("%d",&size);
 
    printf("Enter %d integers\n", size);
 
    for ( c = 0 ; c < size ; c++ )
        scanf("%d", &array[c]);
 
    minimum = array[0];
 
    for ( c = 1 ; c < size ; c++ ) 
    {
        if ( array[c] < minimum ) 
        {
           minimum = array[c];
           location = c+1;
        }
    } 
 
    printf("Minimum element is present at location number %d and it's value is %d.\n", location, minimum);
    return 0;
}

c program to add two numbers using pointers

using pointers

This program performs addition of two numbers using pointers. In our program we have two two integer variables x, y and two pointer variables p and q. Firstly we assign the addresses of x and y to p and q respectively and then assign the sum of x and y to variable sum. Note that & is address of operator and * is value at address operator.

C programming code

#include<stdio.h>
 
main()
{
   int first, second, *p, *q, sum;
 
   printf("Enter two integers to add\n");
   scanf("%d%d", &first, &second);
 
   p = &first;
   q = &second;
 
   sum = *p + *q;
 
   printf("Sum of entered numbers = %d\n",sum);
 
   return 0;
}

c program to print Pascal triangle

scal Triangle in c: C program to print Pascal triangle which you might have studied in Binomial Theorem in Mathematics. Number of rows of Pascal triangle to print is entered by the user. First four rows of Pascal triangle are shown below :-

   1
  1 1
 1 2 1
1 3 3 1 

Pascal triangle in c

#include<stdio.h>
 
long factorial(int);
 
main()
{
   int i, n, c;
 
   printf("Enter the number of rows you wish to see in pascal triangle\n");
   scanf("%d",&n);
 
   for ( i = 0 ; i < n ; i++ )
   {
      for ( c = 0 ; c <= ( n - i - 2 ) ; c++ )
         printf(" ");
 
      for( c = 0 ; c <= i ; c++ )
         printf("%ld ",factorial(i)/(factorial(c)*factorial(i-c)));
 
      printf("\n");
   }
 
   return 0;
}
 
long factorial(int n)
{
   int c;
   long result = 1;
 
   for( c = 1 ; c <= n ; c++ )
         result = result*c;
 
   return ( result );
}

c program to print Floyd's triangle

C program to print Floyd's triangle:- This program prints Floyd's triangle. Number of rows of Floyd's triangle to print is entered by the user. First four rows of Floyd's triangle are as follows :-
1
2 3
4 5 6
7 8 9 10
It's clear that in Floyd's triangle nth row contains n numbers.

C programming code

#include <stdio.h>
 
int main()
{
  int n, i,  c, a = 1;
 
  printf("Enter the number of rows of Floyd's triangle to print\n");
  scanf("%d", &n);
 
  for (i = 1; i <= n; i++)
  {
    for (c = 1; c <= i; c++)
    {
      printf("%d ",a);
      a++;
    }
    printf("\n");
  }
 
  return 0;
}

Fibonacci series program in c using recursion

#include<stdio.h>
 
int Fibonacci(int);
 
main()
{
   int n, i = 0, c;
 
   scanf("%d",&n);
 
   printf("Fibonacci series\n");
 
   for ( c = 1 ; c <= n ; c++ )
   {
      printf("%d\n", Fibonacci(i));
      i++; 
   }
 
   return 0;
}
 
int Fibonacci(int n)
{
   if ( n == 0 )
      return 0;
   else if ( n == 1 )
      return 1;
   else
      return ( Fibonacci(n-1) + Fibonacci(n-2) );
} 

Fibonacci series in c

Fibonacci series in c programming: c program for Fibonacci series without and with recursion. Using the code below you can print as many number of terms of series as desired. Numbers of Fibonacci sequence are known as Fibonacci numbers. First few numbers of series are 0, 1, 1, 2, 3, 5, 8 etc, Except first two terms in sequence every other term is the sum of two previous terms, For example 8 = 3 + 5 (addition of 3, 5). This sequence has many applications in mathematics and Computer Science.

Fibonacci series in c using for loop

 

 

/* Fibonacci Series c language */
#include<stdio.h>
 
main()
{
   int n, first = 0, second = 1, next, c;
 
   printf("Enter the number of terms\n");
   scanf("%d",&n);
 
   printf("First %d terms of Fibonacci series are :-\n",n);
 
   for ( c = 0 ; c < n ; c++ )
   {
      if ( c <= 1 )
         next = c;
      else
      {
         next = first + second;
         first = second;
         second = next;
      }
      printf("%d\n",next);
   }
 
   return 0;
}

 

c program to generate and print armstrong numbers

armstrong number in c: This program prints armstrong number. In our program we ask the user to enter a number and then we use a loop from one to the entered number and check if it is an armstrong number and if it is then the number is printed on the screen. Remember a number is armstrong if the sum of cubes of individual digits of a number is equal to the number itself. For example 371 is an armstrong number as 3³ + 7³ + 1³ = 371. Some other armstrong numbers are 0, 1, 153, 370, 407.

C code

 

 

#include<stdio.h>
#include<conio.h>
 
main()
{
   int r;
   long number = 0, c, sum = 0, temp;
 
   printf("Enter the maximum range upto which you want to find armstrong numbers ");
   scanf("%ld",&number);
 
   printf("Following armstrong numbers are found from 1 to %ld\n",number);
 
   for( c = 1 ; c <= number ; c++ )
   {
      temp = c;
      while( temp != 0 )
      {
         r = temp%10;
         sum = sum + r*r*r;
         temp = temp/10;
      }
      if ( c == sum )
         printf("%ld\n", c);
      sum = 0;
   }
 
   getch();
   return 0;
}

 

armstrong number c program

armstrong number c program: c programming code to check whether a number is armstrong or not. A number is armstrong if the sum of cubes of individual digits of a number is equal to the number itself. For example 371 is an armstrong number as 3³ + 7³ + 1³ = 371. Some other armstrong numbers are: 0, 1, 153, 370, 407.

#include <stdio.h>
 
main()
{
   int number, sum = 0, temp, remainder;
 
   printf("Enter a number\n");      
   scanf("%d",&number);
 
   temp = number;
 
   while( temp != 0 )
   {
      remainder = temp%10;
      sum = sum + remainder*remainder*remainder;
      temp = temp/10; 
   }
 
   if ( number == sum )
      printf("Entered number is an armstrong number.");
   else
      printf("Entered number is not an armstrong number.");         
 
   return 0;
}

c program to print diamond pattern

#include <stdio.h>
 
int main()
{
  int n, c, k, space = 1;
 
  printf("Enter number of rows\n");
  scanf("%d", &n);
 
  space = n - 1;
 
  for (k = 1; k <= n; k++)
  {
    for (c = 1; c <= space; c++)
      printf(" ");
 
    space--;
 
    for (c = 1; c <= 2*k-1; c++)
      printf("*");
 
    printf("\n");
  }
 
  space = 1;
 
  for (k = 1; k <= n - 1; k++)
  {
    for (c = 1; c <= space; c++)
      printf(" ");
 
    space++;
 
    for (c = 1 ; c <= 2*(n-k)-1; c++)
      printf("*");
 
    printf("\n");
  }
 
  return 0;
}

C program for prime number using function

#include<stdio.h>
 
int check_prime(int);
 
main()
{
   int n, result;
 
   printf("Enter an integer to check whether it is prime or not.\n");
   scanf("%d",&n);
 
   result = check_prime(n);
 
   if ( result == 1 )
      printf("%d is prime.\n", n);
   else
      printf("%d is not prime.\n", n);
 
   return 0;
}
 
int check_prime(int a)
{
   int c;
 
   for ( c = 2 ; c <= a - 1 ; c++ )
   { 
      if ( a%c == 0 )
  return 0;
   }
   if ( c == a )
      return 1;
}

C program for prime number or not

#include<stdio.h>
 
main()
{
   int n, c = 2;
 
   printf("Enter a number to check if it is prime\n");
   scanf("%d",&n);
 
   for ( c = 2 ; c <= n - 1 ; c++ )
   {
      if ( n%c == 0 )
      {
         printf("%d is not prime.\n", n);
  break;
      }
   }
   if ( c == n )
      printf("%d is prime.\n", n);
 
   return 0;
}

c program for prime number

Prime number program in c: c program for prime number, this code prints prime numbers using c programming language. To check whether a number is prime or not see another code below. Prime number logic: a number is prime if it is divisible only by one and itself. Remember two is the only even and also the smallest prime number. First few prime numbers are 2, 3, 5, 7, 11, 13, 17....etc. Prime numbers have many applications in computer science and mathematics. A number greater than one can be factorized into prime numbers, For example 540 = 2²*3³*5¹

#include<stdio.h>
 
main()
{
   int n, i = 3, count, c;
 
   printf("Enter the number of prime numbers required\n");
   scanf("%d",&n);
 
   if ( n >= 1 )
   {
      printf("First %d prime numbers are :\n",n);
      printf("2\n");
   }
 
   for ( count = 2 ; count <= n ;  )
   {
      for ( c = 2 ; c <= i - 1 ; c++ )
      {
         if ( i%c == 0 )
            break;
      }
      if ( c == i )
      {
         printf("%d\n",i);
         count++;
      }
      i++;
   }         
 
   return 0;
}

pattern

Consider the pattern
*
**
***
****
*****..

#include<stdio.h>
 
main()
{
    int n, c, k;
 
    printf("Enter number of rows\n");
    scanf("%d",&n);
 
    for ( c = 1 ; c <= n ; c++ )
    {
        for( k = 1 ; k <= c ; k++ )
            printf("*");
 
        printf("\n");
    }
 
    return 0;
}

c program to print patterns of numbers and stars

These program prints various different patterns of numbers and stars. These codes illustrate how to create various patterns using c programming. Most of these c programs involve usage of nested loops and space. A pattern of numbers, star or characters is a way of arranging these in some logical manner or they may form a sequence. Some of these patterns are triangles which have special importance in mathematics. Some patterns are symmetrical while other are not. Please see the complete page and look at comments for many different patterns.

    *
   ***
  *****
 *******
*********

We have shown five rows above, in the program you will be asked to enter
 the numbers of rows you want to print in the pyramid of stars.

 #include<stdio.h>
 
main()
{
   int row, c, n, temp;
 
   printf("Enter the number of rows in pyramid of stars you wish to see ");
   scanf("%d",&n);
 
   temp = n;
 
   for ( row = 1 ; row <= n ; row++ )
   {
      for ( c = 1 ; c < temp ; c++ )
         printf(" ");
 
      temp--;
 
      for ( c = 1 ; c <= 2*row - 1 ; c++ )
         printf("*");
 
      printf("\n");
   }
 
   return 0;
}

Palindrome Numbers

Palindrome number in c: A palindrome number is a number such that if we reverse it, it will not change. For example some palindrome numbers examples are 121, 212, 12321, -454. To check whether a number is palindrome or not first we reverse it and then compare the number obtained with the original, if both are same then number is palindrome otherwise not. C program for palindrome number is given below.

Palindrome number algorithm

1. Get the number from user.
2. Reverse it.
3. Compare it with the number entered by the user.
4. If both are same then print palindrome number
5. Else print not a palindrome number.

Palindrome number program c

 

#include<stdio.h>
 
main()
{
   int n, reverse = 0, temp;
 
   printf("Enter a number to check if it is a palindrome or not\n");
   scanf("%d",&n);
 
   temp = n;
 
   while( temp != 0 )
   {
      reverse = reverse * 10;
      reverse = reverse + temp%10;
      temp = temp/10;
   }
 
   if ( n == reverse )
      printf("%d is a palindrome number.\n", n);
   else
      printf("%d is not a palindrome number.\n", n);
 
   return 0;
}

 

c program to reverse a number

C Program to reverse a number :- This program reverse the number entered by the user and then prints the reversed number on the screen. For example if user enter 123 as input then 321 is printed as output. In our program we use modulus(%) operator to obtain the digits of a number. To invert number look at it and write it from opposite direction or the output of code is a number obtained by writing original number from right to left. To reverse large numbers use long data type or long long data type if your compiler supports it, if you still have large numbers then use strings or other data structure.

#include <stdio.h>
 
main()
{
   int n, reverse = 0;
 
   printf("Enter a number to reverse\n");
   scanf("%d",&n);
 
   while (n != 0)
   {
      reverse = reverse * 10;
      reverse = reverse + n%10;
      n = n/10;
   }
 
   printf("Reverse of entered number is = %d\n", reverse);
 
   return 0;
}

C programming code to swap using bitwise XOR

#include <stdio.h>
 
int main()
{
  int x, y;
 
  scanf("%d%d", &x, &y);
 
  printf("x = %d\ny = %d\n", x, y);
 
  x = x ^ y;
  y = x ^ y;
  x = x ^ y;
 
  printf("x = %d\ny = %d\n", x, y);
 
  return 0;
}

Swapping numbers using call by reference

In this method we will make a function to swap numbers.

#include <stdio.h>
 
void swap(int*, int*);
 
int main()
{
   int x, y;
 
   printf("Enter the value of x and y\n");
   scanf("%d%d",&x,&y);
 
   printf("Before Swapping\nx = %d\ny = %d\n", x, y);
 
   swap(&x, &y); 
 
   printf("After Swapping\nx = %d\ny = %d\n", x, y);
 
   return 0;
}
 
void swap(int *a, int *b)
{
   int temp;
 
   temp = *b;
   *b = *a;
   *a = temp;   
}

Swap two numbers using pointers

#include <stdio.h>
 
int main()
{
   int x, y, *a, *b, temp;
 
   printf("Enter the value of x and y\n");
   scanf("%d%d", &x, &y);
 
   printf("Before Swapping\nx = %d\ny = %d\n", x, y);
 
   a = &x;
   b = &y;
 
   temp = *b;
   *b = *a;
   *a = temp;
 
   printf("After Swapping\nx = %d\ny = %d\n", x, y);
 
   return 0;
}

Swapping of two numbers without third variable

You can also swap two numbers without using temp or temporary or third variable. In that case c program will be as shown :-

#include <stdio.h>
 
int main()
{
   int a, b;
 
   printf("Enter two integers to swap\n");
   scanf("%d%d", &a, &b);
 
   a = a + b;
   b = a - b;
   a = a - b;
 
   printf("a = %d\nb = %d\n",a,b);
   return 0;
}

c program to swap two numbers

C program to swap two numbers with and without using third variable, swapping in c using pointers, functions (Call by reference) and using bitwise XOR operator, swapping means interchanging. For example if in your c program you have taken two variable a and b where a = 4 and b = 5, then before swapping a = 4, b = 5 after swapping a = 5, b = 4
In our c program to swap numbers we will use a temp variable to swap two numbers. Swapping is used in sorting that is when we wish to arrange numbers in a particular order either in ascending order or in descending order.

Swapping of two numbers in c

 

#include <stdio.h>
 
int main()
{
   int x, y, temp;
 
   printf("Enter the value of x and y\n");
   scanf("%d%d", &x, &y);
 
   printf("Before Swapping\nx = %d\ny = %d\n",x,y);
 
   temp = x;
   x = y;
   y = temp;
 
   printf("After Swapping\nx = %d\ny = %d\n",x,y);
 
   return 0;
}

 

c program to add n numbers

This c program add n numbers which will be entered by the user. Firstly user will enter a number indicating how many numbers user wishes to add and then user will enter n numbers. In the first c program to add numbers we are not using an array, and using array in the second code.

C programming code

 

#include <stdio.h>
 
int main()
{
   int n, sum = 0, c, value;
 
   printf("Enter the number of integers you want to add\n");
   scanf("%d", &n);
 
   printf("Enter %d integers\n",n);
 
   for (c = 1; c <= n; c++)
   {
      scanf("%d",&value);
      sum = sum + value;
   }
 
   printf("Sum of entered integers = %d\n",sum);
 
   return 0;
}

 

c program to find ncr and npr

program to find nCr and nPr: This code calculate nCr which is n!/(r!*(n-r)!) and nPr = n!/(n-r)!

C program to find nCr using function

 

#include<stdio.h>
 
long factorial(int);
long find_ncr(int, int);
long find_npr(int, int);
 
main()
{
   int n, r;
   long ncr, npr;
 
   printf("Enter the value of n and r\n");
   scanf("%d%d",&n,&r);
 
   ncr = find_ncr(n, r);
   npr = find_npr(n, r);
 
   printf("%dC%d = %ld\n", n, r, ncr);
   printf("%dP%d = %ld\n", n, r, npr);
 
   return 0;
}
 
long find_ncr(int n, int r)
{
   long result;
 
   result = factorial(n)/(factorial(r)*factorial(n-r));
 
   return result;
}
 
long find_npr(int n, int r)
{
   long result;
 
   result = factorial(n)/factorial(n-r);
 
   return result;
} 
 
long factorial(int n)
{
   int c;
   long result = 1;
 
   for( c = 1 ; c <= n ; c++ )
      result = result*c;
 
   return ( result );
}