//1351
#include<iostream>

using namespace std;

int judge(int a, int b, int c){
    return b*b+c*c-a*a;
}

int main()
{
    int a, b, c;
    while(cin>>a>>b>>c){
        if(b > a)
            swap(a, b);
        if(c > a)
            swap(a, c);
        int s = judge(a, b, c);
        if(s > 0)
            cout << "锐角三角形" << endl;
        if(s == 0)
            cout << "直角三角形" << endl;
        if(s < 0)
            cout << "钝角三角形" << endl;
    }

    return 0;
}