public static void Main()
double number1,number2,number3,number4;
Console.Write("Input number1 =");
number1 = Convert.ToInt32(Console.ReadLine());
Console.Write( "Enter number2 =");
number2 = Convert.ToInt32(Console.ReadLine());
Console.Write( "Enter number3=");
number3= Convert.ToInt32(Console.ReadLine());
Console.Write("Enter number4 = ");
number4 = Convert.ToInt64(Console.ReadLine());
double avg= (number1 + number2 + number3 + number4) / 4;
Console.WriteLine("Average = "+avg);