Stuck Numbers

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

namespace _09StuckNumbers
{
    class Program
    {
        static void Main(string[] args)
        {
            int n = int.Parse(Console.ReadLine());
            List<string> numbers = Console.ReadLine().Split(' ').Where(s => !string.IsNullOrWhiteSpace(s)).ToList();
            List<string> numbersTemp = numbers;
            int count = 0;
            if (n < 4)
            {
                Console.WriteLine("No");
                return;
            }
            foreach (string a in numbers)
            {
                numbersTemp = numbers.ToList();
                numbersTemp.Remove(a);
                foreach (string b in numbersTemp.ToList())
                {
                    numbersTemp.Remove(b);
                    foreach (string c in numbersTemp.ToList())
                    {
                        numbersTemp.Remove(c);
                        foreach (string d in numbersTemp)
                        {
                            if (a + b == c + d)
                            {
                                Console.WriteLine("{0}|{1}=={2}|{3}", a, b, c, d);
                                count++;
                            }
                        }
                        numbersTemp.Add(c);
                    }
                    numbersTemp.Add(b);
                }
                numbersTemp.Add(a);
            }
            if (count == 0)
            {
                Console.WriteLine("No");
            }

        }
    }
}