#include <iostream>  
using namespace std;
int main() {
    int num;
    cin >> num;
    if (num % 3 == 0) {
        cout << "yes" << endl;
    } else {
        cout << "no" << endl;
    }
    return 0;
}
/**************************************************************
	Problem: 1633
	User: fuhoubin
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/