View Code of Problem 80

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
int main (){
	int n;
	while(~scanf("%d", &n)&&n){
		int s = 0;
		for(int i = 1;i <= n;i++){
			s = (s+3)%i;
		}
		printf("%d\n", s+1);
	}

	return 0;
}