public static void Main(String[] args) { Calculator c = new Calculator(); char a; String val; int n1, n2, ans; Console.Write("Enter integer: "); val = Console.ReadLine(); n1 = Convert.ToInt32(val); Console.Write("Enter integer: "); val = Console.ReadLine(); n2 = Convert.ToInt32(val); Console.Write("Enter operation: "); val = Console.ReadLine(); a = Convert.ToChar(val); switch (a) { case '+': ans = c.Add(n1, n2); Console.WriteLine("result: "); Console.WriteLine(ans); break; case '-': ans = c.Sub(n1, n2); Console.WriteLine("result: "); Console.WriteLine(ans); break; case '*': ans = c.Mul(n1, n2); Console.WriteLine("result: "); Console.WriteLine(ans); break; case '/': ans = c.Div(n1, n2); Console.WriteLine("result: "); Console.WriteLine(ans); break; } Console.ReadKey(); }