Decimal to binary conversion using recursion function in C

/* decimal  to binary conversion using recursion */
#include<stdio.h>
#include<conio.h>
long binary(long  n){
static long int   bin=0,base=1;
if(n>0)
{
printf("%d",n%2);
bin=bin+n%2*base;
base*=10;
binary(n/2);
}
return bin;
}
main(){
long int n=100;
clrscr();
printf("\nbinary no is %ld",binary(n));
}

/* decimal  to binary conversion using loops */

main(){

int no=7;

long  bin=0,base=1;

int d;

while(no)
{
d=no%2;
no/=2;
bin=bin+base*d;
base*=10;
}
printf("\n%d",bin);
}