#include <stdio.h> int main(void){ int a,n; printf("pls input number: "); scanf("%d",&a); n = sizeof(a); int i,c=0; char j[8]; i = a/2; while(i!=0){ j[c]= a%2; a = a/2; c = c+1; } while(c>0){ printf("%d",j[--c]); } return 0; }