Two Numbers Sum

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace TwoNumbersS
{
    class TwoNumbersS
    {
        static void Main(string[] args)
        {
            int startN = int.Parse(Console.ReadLine());
            int endN = int.Parse(Console.ReadLine());
            int magicN = int.Parse(Console.ReadLine());
            int combinations = 0;

            for (int i = startN; i >= endN; i--)
            {
                for (int j = startN; j >= endN; j--)
                {
                    combinations++;
                    if (i + j == magicN)
                    {
                        Console.WriteLine($"Combination N:{combinations} ({i} + {j} = {magicN})");
                        return;
                    }
                }
            }
            Console.WriteLine($"{combinations} combinations - neither equals {magicN}");
        }
    }
}