#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
//#include <windows.h>
//#include <time.h>
#include <vector>
#include <algorithm>

using namespace std;

int main() {
	double a,b,c;
	while(cin>>a>>b>>c) {
		double num[3];
		num[0] = a;
		num[1] = b;
		num[2] = c;
		sort(num,num+3);
		if(num[0]*num[0]+num[1]*num[1] == num[2]*num[2]) {
			cout<<"直角三角形"<<endl;
		} else if(num[0]*num[0]+num[1]*num[1] > num[2]*num[2]) {
			cout<<"锐角三角形"<<endl;
		} else cout<<"钝角三角形"<<endl;
	}
	return 0;
}