/* binary.c -- prints integer in binary form */
#include <stdio.h>void to_binary(unsigned long n);int main(void)
{ unsigned long number; printf("Enter an integer (q to quit):\n"); while (scanf("%ul", &number) == 1) { printf("Binary equivalent: "); to_binary(number); putchar('\n'); printf("Enter an integer (q to quit):\n"); } printf("Done.\n"); return 0;}void to_binary(unsigned long n) /* recursive function */
{ int r;r = n % 2;
if (n >= 2) to_binary(n / 2); putchar('0' + r); return;}