static void Main(string[] args)
float fNum, sNum, result = 0;
Console.WriteLine("Welcome ....");
Console.Write("what's your first number ? : ");
fNum = float.Parse(Console.ReadLine());
Console.Write("what's your operation (+ , - , * , /) ? : ");
operation = char.Parse(Console.ReadLine());
Console.Write("what's your second number ? : ");
sNum = float.Parse(Console.ReadLine());
else if (operation == '-')
else if (operation == '*')
else if (operation == '/')
Console.WriteLine("Result : " + fNum + operation + sNum + " = " + result);
Console.WriteLine("Thanks :)");