#include <iostream>
#include <cmath>

using namespace std;

int main()
{
    float x1, x2, x3, y1, y2, y3, p, a, b, c, h1, h2, h3;

    cout << "Enter coordinates: \n";
    cin >> x1 >> y1 >> x2 >> y2 >> x3 >> y3;

    a = sqrt(pow((x2-x1),2)+pow((y2-y1),2));
    b = sqrt(pow((x3-x2),2)+pow((y3-y2),2));
    c = sqrt(pow((x1-x3),2)+pow((y1-y3),2));

    if (a + b > c && b + c > a && a + c > b)
    {
        if (pow(a, 2) + pow(b, 2) == pow(c, 2) || pow(b,2) + pow (c,2) == pow(a, 2) || pow(a, 2) + pow(c, 2) == pow(b, 2))
            cout << "Right angled triangle";

        else if (
                 (pow(a, 2) - pow(b, 2) - pow(c, 2)) / ((-2)*b*c) > 0 &&
                 (pow(b, 2) - pow(c, 2) - pow(a, 2)) / ((-2)*a*c) > 0 &&
                 (pow(c, 2) - pow(a, 2) - pow(b, 2)) / ((-2)*a*b) > 0
                )
            cout << "Acute-angled triangle\n";

        else cout << "Obtuse-angled triangle\n";
    }
    return 0;
}