#include <iostream>
using namespace std;
int main() {
int a, b, c;
double res = 0;
cin >> a >> b >> c;
res = ((double)a + b + c) / 3;
if(res < 60) cout << "YES" << endl;
else cout << "NO" << endl;
return 0;
}
// 64 位输出请用 printf("%lld")

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