Very interesting task indeed! A lot of stuff is clearing out in my head when it comes to C# and using different methods to solve those kind of tasks!

How I solved this task? Here's how:

• First - the input - we'll need int type and then we will multiply it by itself to get the number of the board desk;
• Then we'll use string for the input - we'll use the string - NOT directly array - because we all know that A PARTICULAR STRING IS AN ARRAY OF CHARACTERS! Very important and useful information!
• Then - the cellsCount will be the board size (boardSize * boardSize);
• It is important to remember that we have a particular condition - and it is: cellsCount > inputString.Length  - otherwise we will have an exception error!
• So we are adding EMPTY additional char with the value of zero 0 (new string(' ', cellsCount - inputString.Length);) as it is stated in the task; After that we are ready for the task itself! 🙂

And the logic for solving the task is:

• We are creating 2 integers - for calculating the black team's and white team's score. Do not forget that when we are going to add a number - we are using 0; and when we are going to multiply - we use 1 (do NOT mix them!)
• We need for loop and it's size will be the cellsCount (boardSize * boardSize);
• In the for loop - we are creating char currentChar which is an element of the inputString[letter] - we are using letter in the square brackets for the number of the inputString; This line: char currentChar = inputString[letter]; in my opinion is crucial!
• Then we have 3 conditions in order to calculate the sum of the chars (use ASCII table -  https://www.asciitable.com/  - we need to have: ((currentChar >= 'a' && currentChar <= 'z') ||(currentChar >= 'A' && currentChar <= 'Z') ||(currentChar >= '0' && currentChar <= '9'))
• ...and then 2 conditions for the odd (letter % 2 != 0) or even number (letter % 2 == 0) - to know for which team we are going to add the scores.
• Then some if/else for the capital letters from the task's explanation.
• And at the end - just print the results! 🙂

Interesting and really amazing task! thanks, Jolie for sharing it with the community!

Here is the code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
 
class ChessboardGame
{
    static void Main()
    {
        int boardSize = int.Parse(Console.ReadLine());
        string inputString = Console.ReadLine();
 
        int cellsCount = boardSize * boardSize;
        if (cellsCount > inputString.Length)
        {
            string additionalCharacters = new string(' ', cellsCount - inputString.Length);
            inputString = inputString + additionalCharacters;
        }
 
        int blackTeamScore = 0;
        int whiteTeamScore = 0;
 
        for (int letter = 0; letter < cellsCount; letter++)
        {
            char currentChar = inputString[letter];
 
            if ((currentChar >= 'a' && currentChar <= 'z') ||
                (currentChar >= 'A' && currentChar <= 'Z') ||
                (currentChar >= '0' && currentChar <= '9'))
            {
                if (letter % 2 == 0)
                {
                    if (currentChar >= 'A' && currentChar <= 'Z')
                    {
                        whiteTeamScore += currentChar;
                    }
                    else
                    {
                        blackTeamScore += currentChar;
                    }
                }
                else if (letter % 2 != 0)
                {
                    if (currentChar >= 'A' && currentChar <= 'Z')
                    {
                        blackTeamScore += currentChar;
                    }
                    else
                    {
                        whiteTeamScore += currentChar;
                    }
                }
            }
        }
        if (blackTeamScore > whiteTeamScore)
        {
            Console.WriteLine("The winner is: black team");
            Console.WriteLine(blackTeamScore - whiteTeamScore);
        }
        if (whiteTeamScore > blackTeamScore)
        {
            Console.WriteLine("The winner is: white team");
            Console.WriteLine(whiteTeamScore - blackTeamScore);
        }
        else if (blackTeamScore == whiteTeamScore)
        {
            Console.WriteLine("Equal result: {0}", whiteTeamScore);
        }
    }
}