#include <iostream.h>

using namespace std;

int main() {
	int a, b, c;
	cin >> a;
	cin >> b;
	cin >> c;
	if ((a+b)>=c) {
			cout << 'it is triangle';
		}
	if ((a+b)<c) {
			cout << 'it is not a triangle';
		}
	return 0;
}