#include <iostream>
using namespace std;

int main() {
	int a, b, c;
	cin >> a >> b >> c;
	float average = (a + b + c) / 3.0;
	if (average >= 60) {
		cout << "NO" << endl;
	}
	else {
		cout << "YES" << endl;
	}

	system("pause");
	return 0;
 }