//以2进制打印整数

#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_s("%lu",&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)

{

int r;

r=n%2;

if(n>=2)

to_binary(n/2);

putchar(r==0?'0':'1');

return;

}