How to sum of diagonal elements of a mxn matrix in C#

Write a program in C# that finds the sum of diagonal elements of a mxn matrix.

Following is the simple C# code :

class Lab
    {
        static void Main(string[] args)
        {
            int h, v, rows, cols;
            int[,] myArray = new int[50, 50];

            Console.WriteLine("Enter Row Value");
            rows = Convert.ToInt32(Console.ReadLine());
            Console.WriteLine("Enter Column Value");
            cols = Convert.ToInt32(Console.ReadLine());
            Console.WriteLine("Enter Elements one by one");
            for (h = 1; h <= rows; h++)
            {
                for (v = 1; v <= cols; v++)
                {
                    myArray[h, v] = Convert.ToInt32(Console.ReadLine());
                }
            }
            Console.WriteLine("Given Matrix");
            for (h = 1; h <= rows; h++)
            {
                for (v = 1; v <= cols; v++)
                {
                    Console.Write("\t{0}", myArray[h, v]);
                }
                Console.WriteLine();
            }

            int digonalSum1 = 0;
            int digonalSum2 = 0;
            if (rows == cols)
            {
                for (h = 1; h <= rows; h++)
                {

                    for (v = 1; v <= cols; v++)
                    {
                        if (h == v)
                        {
                            digonalSum1 = digonalSum1 + myArray[h, v];
                        }

                    }

                    digonalSum2 = digonalSum2 + myArray[h, cols - h + 1];
                }
                Console.WriteLine("Diagonal Sum= {0}", digonalSum1);
                Console.WriteLine("Diagonal Sum= {0}", digonalSum2);
            }
            else
            {
                Console.WriteLine("Can't Perform Diagonal Sum");
            }
            Console.Read();

        }
    }

Output:-

Enter Row Value
2
Enter Column Value
2
Enter Elements one by one
1
2
3
4

Given Matrix
        1       2
        3       4

Diagonal Sum= 5
Diagonal Sum= 5