#6695: TLE~~嗚嗚..
cse011417
(哈哈哈)
#include<iostream>
#define MAX 10001
using namespace std;
int main()
{
int b=0;
int i;
char s[MAX],a[1]="";
while(1)
{
cin>>s;
for (i=0; s[i]!=a[0]; i++)
{
b+=(s[i]-'0');
}
if(b%3==0)
{
cout<<"yes";
}
else
{
cout<<"no";
}
cout<<endl;
b=0;
}
}