diagdifference.cs

using System.CodeDom.Compiler;
using System.Collections.Generic;
using System.Collections;
using System.ComponentModel;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Runtime.Serialization;
using System.Text.RegularExpressions;
using System.Text;
using System;

class Result
{

    /*
     * Complete the 'diagonalDifference' function below.
     *
     * The function is expected to return an INTEGER.
     * The function accepts 2D_INTEGER_ARRAY arr as parameter.
     */ //

    public static int diagonalDifference(List<List<int>> arr)
    {
        int difference = 0;
        int sum1 = 0;
        int sum2 = 0;
        for (int i = 0; i < arr.Count; i++)
        {
            sum1 = sum1 + arr[i][i];
        }
        for (int i = 0; i < arr.Count; i++)
        {
            for (int i2 = arr.Count-1; i2 >= 0; i2--)
            {
                if (i + i2 == arr.Count - 1)
                {
                    sum2 = sum2 + arr[i][i2];
                }
            }
            difference = sum2 - sum1;
        }
        return Math.Abs(difference);
    }
}

class Solution
{
    public static void Main(string[] args)
    {
        TextWriter textWriter = new StreamWriter(@System.Environment.GetEnvironmentVariable("OUTPUT_PATH"), true);

        int n = Convert.ToInt32(Console.ReadLine().Trim());

        List<List<int>> arr = new List<List<int>>();

        for (int i = 0; i < n; i++)
        {
            arr.Add(Console.ReadLine().TrimEnd().Split(' ').ToList().Select(arrTemp => Convert.ToInt32(arrTemp)).ToList());
        }

        int result = Result.diagonalDifference(arr);

        textWriter.WriteLine(result);

        textWriter.Flush();
        textWriter.Close();
    }
}