C programm : Decimal to binary conversion

C program to convert decimal to binary: c language code to convert an integer from decimal number system(base-10) to binary number system(base-2). Size of integer is assumed to be 32 bits. We use bitwise operators to perform the desired task. We right shift the original number by 31, 30, 29, ..., 1, 0 bits using a loop and bitwise AND the number obtained with 1(one), if the result is 1 then that bit is 1 otherwise it is 0(zero). 

#include <stdio.h>
 
int main()
{
  int n, c, k;
 
  printf("Enter an integer in decimal number system\n");
  scanf("%d", &n);
 
  printf("%d in binary number system is:\n", n);
 
  for (c = 31; c >= 0; c--)
  {
    k = n >> c;
 
    if (k & 1)
      printf("1");
    else
      printf("0");
  }
 
  printf("\n");
 
  return 0;
}

Above code only prints binary of integer, but we may wish to perform 
operations on binary so in the code below we are storing the binary in a
 string. We create a function which returns a pointer to string which is
 the binary of the number passed as argument to the function.