using System;
using System.Collections.Generic;
using System.Text;

namespace Triangle
{
    // All the triangle types.
    public enum TriangleType
    {
        NotTriangle,    // Bad / Illegal Triangle
        Scalene,        // All sides have different size
        Isosceles,      // Two sides are equivalent, the ther is different
        Equilateral     // All sides are equal
    }

    // Triangle Class:
    //  - Has sides widths, ordered.
    //  - Says the triangle dimensions.
    //  - Says the type of the triangle.
    public class Triangle
    {
        // Sides widths
        public int[] sides;

        public Triangle(int A, int B, int C)
        {
            sides = new int[3]; // No need to delete dynamic allocations in C#. Wow.
            sides[0] = A;
            sides[1] = B;
            sides[2] = C;
        }

        public Triangle()
        {
            sides = new int[3];
        }

        // Returns the type of the triangle.
        //  Rule:
        //      - All triangles are not legal triangles until proven the contrary;
        //      - Easiest check: Equilateral (sides are equal);
        //      - As long as dimensions proportions are fine:
        //          - If there is any equivalence between sides and it is NOT an equilateral, it must be an Isosceles;
        //          - If all the above failed, it is a Scalene.
        public TriangleType SayType()
        {
            // Sorting the sides' width is the best way I could think for determining the type.
            Array.Sort(sides);

            TriangleType Type = TriangleType.NotTriangle;
            if (sides[0] == sides[1] && sides[0] == sides[2])
            {
                Type = TriangleType.Equilateral;
                // Test Hint: we don;t check for 0 values
            }
            else if (sides[0] + sides[1] > sides[2])
            {
                if (sides[0] == sides[1] || sides[1] == sides[2])
                {
                    Type = TriangleType.Isosceles;
                    // Test Hint: We don't check for negative numbers...
                }
                else
                {
                    Type = TriangleType.Scalene;
                    // Testing Hint: What else falls in this category?
                }
            }
            else
            {
                Type = TriangleType.NotTriangle;
            }
            return Type;
        }
    }
}