#include<bits/stdc++.h>
using namespace std;
int main(){
    int a;
    cin>>a;
    if(a%3==0){
        cout<<"yes";
    }else{
        cout<<"no";
    }
}
/**************************************************************
	Problem: 1633
	User: wngjinming
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/