public static void Main()
Random randomNumber = new Random();
int size = randomNumber.Next(0, 100);
int[] mass = new int[size];
for(int i=0; i<mass.Length; i++)
mass[i] = randomNumber.Next(0, 1000001);
Console.WriteLine("[{0}] = {1}", i, mass[i]);
Console.WriteLine("\nСума усіх {0} чисел = {1}", mass.Length, sum);