#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: sucongyi
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/