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CSharp · Console

/Program.cs

using System;
					
public class Program
{
	public static void Main()
	{
    
        Random rand = new Random();
        Console.WriteLine("Введите размерность матрици MxM :");
        int M = Convert.ToInt32(Console.ReadLine());
        int[,] matrix = new int[M, M];
        for (int j = 0; j < M; j++)
        {
            for (int m = 0; m < M; m++)
            {
                matrix[j, m] = rand.Next(0, 10);
                Console.Write(matrix[j, m] + " "); 
            }
            Console.WriteLine();


		}
		
		
		
		var sum = 0;
		
		for(int i = 0; i < M; i++){
		
			if(i%2 == 0){
			
				for(int j =0; j < M ; j++){
					
					sum+= matrix[i,j];
				}
				
			}
			
		}
		
		Console.WriteLine(sum);
		
		
	}
}