using System;

public class Program

{

    public static void Main()

    {

        int a = 5;

        int b = 7;

        string suma = "La suma es: " + (a + b);

        Console.WriteLine(suma);

        string incorrecto = "La suma es: " + a + b;

        Console.WriteLine(incorrecto);

        Console.WriteLine("Perimetro = " + 2

                         * (a + b) + ". Area = "

                         + (a * b) + ".");

    }

}