public static void Main()
int[, ] arr = new int[4, 5];
for (int i = 0; i < arr.GetLength(0); i++)
for (int j = 0; j < arr.GetLength(1); j++)
for (int i = 0; i < arr.GetLength(0); i++)
for (int j = 0; j < arr.GetLength(1); j++)
Console.Write(arr[i, j] + " ");