4.NakovsMatching.cs

using System;
using System.Collections.Generic;
using System.Linq;

class NakovMatching
{
    static void Main()
    {
        string word1 = Console.ReadLine();
        string word2 = Console.ReadLine();
        long diff = long.Parse(Console.ReadLine());

        List<char> char1 = word1.ToList();
        List<char> char2 = word2.ToList();

        bool check = false;
        long nakovs = 0;
        long firstSum1 = 0;
        long firstSum2 = 0;
        long firstWeight = 0;
        long secondSum1 = 0;
        long secondSum2 = 0;
        long secondWeight = 0;
        string print1 = "";
        string print2 = "";

        for (int i = 0; i < word1.Length - 1; i++)
        {
            char1.Insert(i + 1, '|');
            firstSum1 = FindSum1(char1, firstSum1);
            firstSum2 = FindSum2(char1, firstSum2);
            for (int k = 0; k < word2.Length - 1; k++)
            {
                char2.Insert(k + 1, '|');
                secondSum1 = FindSum1(char2, secondSum1);
                secondSum2 = FindSum2(char2, secondSum2);
                firstWeight = firstSum1 * secondSum2;
                secondWeight = firstSum2 * secondSum1;
                if (Math.Abs(firstWeight - secondWeight) <= diff)
                {
                    for (int l = 0; l < word1.Length + 1; l++)
                    {
                        print1 += char1[l];
                    }
                    for (int p = 0; p < word2.Length + 1; p++)
                    {
                        print2 += char2[p];
                    }
                    nakovs = (Math.Abs(firstWeight - secondWeight));
                    Console.WriteLine("({0}) matches ({1}) by {2} nakovs", print1, print2, nakovs);
                    check = true;
                }
                firstWeight = 0;
                nakovs = 0;
                secondSum1 = 0;
                secondSum2 = 0;
                secondWeight = 0;
                print2 = "";
                char2 = word2.ToList();
                print1 = "";
            }
            firstSum1 = 0;
            firstSum2 = 0;
            char1 = word1.ToList();
        }
        if (check == false)
        {
            Console.WriteLine("No");
        }
    }

    private static long FindSum2(List<char> char1, long sum2)
    {
        char1.Reverse();
        for (int o = 0; o < 900; o++)
        {
            if (char1[o] == '|')
            {
                break;
            }
            sum2 += char1[o];
        }
        char1.Reverse();
        return sum2;
    }

    private static long FindSum1(List<char> char1, long sum1)
    {
        for (int o = 0; o < 900; o++)
        {
            if (char1[o] == '|')
            {
                break;
            }
            sum1 += char1[o];
        }
        return sum1;
    }
}