//swap的用法排序，
//以及已经排序了所以最后一个只需要考虑a==b&&b!==c与b==c&&b=!=a,不用考虑a==c
#include <iostream>
using namespace std;
int main()
{
    double a, b, c;
    cin >> a >> b >> c;
    if (a < b) swap(a, b);
    if (a < c) swap(a, c);
    if (b < c) swap(b, c);
    if (a >= b + c) 
    cout << "NAO FORMA TRIANGULO" << endl;
    else
    {
        if (a * a == b * b + c * c) 
            cout << "TRIANGULO RETANGULO" << endl;
        if (a * a > b * b + c * c)
            cout << "TRIANGULO OBTUSANGULO" << endl;
        if (a * a < b * b + c * c) 
            cout << "TRIANGULO ACUTANGULO" << endl;
        if (a == b && a == c) 
            cout << "TRIANGULO EQUILATERO" << endl;
        if((a==b&&b!=c )|| (b==c&&a!=b))
            cout << "TRIANGULO ISOSCELES" << endl;
    }
    return 0;
}