04_NakovsMatching

using System;
using System.Collections.Generic;

class NakovsMatching
{
    static void Main()
    {
        string firstWord = Console.ReadLine();
        string secondWord = Console.ReadLine();
        long d = long.Parse(Console.ReadLine());
        bool matchFound = false;

        for (int i = 0; i < firstWord.Length - 1; i++)
        {
            long firstWordLeftSum = 0;
            long firstWordRightSum = 0;
            List<char> firstLeft = new List<char>();
            List<char> firstRight = new List<char>();
            int rightStartIndexFirstWord = i + 1;

            for (int k = 0; k < rightStartIndexFirstWord; k++)
            {
                firstWordLeftSum += firstWord[k];
                firstLeft.Add(firstWord[k]);
            }
            for (int m = rightStartIndexFirstWord; m < firstWord.Length; m++)
            {
                firstWordRightSum += firstWord[m];
                firstRight.Add(firstWord[m]);
            }
            for (int j = 0; j < secondWord.Length - 1; j++)
            {
                long secondWordLeftSum = 0;
                long secondWordRightSum = 0;
                List<char> secondLeft = new List<char>();
                List<char> secondRight = new List<char>();
                int rightStartIndexSecondWord = j + 1;

                for (int n = 0; n < rightStartIndexSecondWord; n++)
                {
                    secondWordLeftSum += secondWord[n];
                    secondLeft.Add(secondWord[n]);
                }
                for (int p = rightStartIndexSecondWord; p < secondWord.Length; p++)
                {
                    secondWordRightSum += secondWord[p];
                    secondRight.Add(secondWord[p]);
                }
                long diff = Math.Abs(firstWordLeftSum * secondWordRightSum - firstWordRightSum * secondWordLeftSum);
                if (diff <= d)
                {
                    string firstResult = string.Join("", firstLeft) + "|" + string.Join("", firstRight);
                    string secondResult = string.Join("", secondLeft) + "|" + string.Join("", secondRight);
                    Console.WriteLine("({0}) matches ({1}) by {2} nakovs", firstResult, secondResult, diff);
                    matchFound = true;
                }
            }
        }
        if (matchFound == false)
        {
            Console.WriteLine("No");
        }
    }
}