#include <iostream>
#include <math.h>

using namespace std;

int main ()
{
    int x = 0, y = 0, z = 0;
    double a, aa, b, bb, c, cc;
    
    cout << "Put the lengths of each side of a triangle to determine what type it is.\n\n";
    
    cout << "Length of the first side : ";
    cin  >> x;
    cout << "Length of the second side: ";
    cin  >> y;
    cout << "Length of the third side : ";
    cin  >> z;

    if ( x != 0 && y != 0 && z != 0 )
    {
       if ( x + y > z || x + z > y || y + z > x )
       {
          a  = pow(x, 2) + pow(y, 2);
          aa = pow(z, 2);
          b  = pow(x, 2) + pow(z, 2);
          bb = pow(y, 2);
          c  = pow(y, 2) + pow(z, 2);
          cc = pow(x, 2);
       
          if ( a == aa || b == bb || c == cc )
              cout << "This is a right triangle.\n";
          else if( x != y && x != z )
               cout << "This is a scalene triangle.\n";
          else
              cout << "This is a isosceles triangle.\n";
       }
    }
    else 
         cout << "All three lengths must be entered.";

    return 0;
}