#include<bits/stdc++.h>
using namespace std;
int main() {
    int a, b, c;
    cin >> a >> b >> c;
    if(a + c <= b || a + b <= c || c + b <= a) {
        cout << "not a triangle" << endl;
    } else if(a * a + c * c == b * b || a * a + b * b == c * c || b * b + c * c == a * a) {
        cout << "yes" << endl;
    } else {
        cout << "no" << endl;
    }
    return 0;
}