View Code of Problem 80

    #include <iostream>
    using namespace std;
    int main(){
    	int n;
    	while(cin>>n&&n){
    		int s=0;
    		for(int i=1;i<=n;i++){
    			s=(s+3)%i;
    		}
    		cout<<s+1<<endl;
    	}
    }