#include<bits/stdc++.h>
using namespace std;
int main(){
	int a,b,c;
	cin>>a>>b>>c;
	if(5+6>c){
		cout<<"yes"<<endl;
	}else {
		cout<<"no"<<endl;
	}
	return 0;
}
/**************************************************************
	Problem: 1036
	User: HUANGYIBO
	Language: C++
	Result: Wrong Answer
****************************************************************/