using System;

public class Program

{

    public static void Main()

    {

        Console.Write("Ingrese la Cal. 1 : ");

        int n1 = Convert.ToInt16(Console.ReadLine());

        Console.Write("Ingrese la Cal. 2 : ");

        int n2 = Convert.ToInt16(Console.ReadLine());

        Console.Write("Ingrese la Cal. 3 : ");

        int n3 = Convert.ToInt16(Console.ReadLine());

        int P = (n1 + n2 + n3)/3;

        // Calculamos el promedio de las calificaciones

        Console.WriteLine("El promedio es: {0}", P);

    }

}