#include<bits/stdc++.h>
using namespace std;
int main(){
int a;
cin>>a;
if(a%3==0){
cout<<"yes";
}else cout<<"no";
return 0;
}
/**************************************************************
Problem: 1633
User: toughuatao1
Language: C++
Result: Accepted
Time:7 ms
Memory:2072 kb
****************************************************************/