using System;

public class Program

{

    public static void Main(string[] args)

    {

        Console.Write("Input a = ");

        int a = int.Parse(Console.ReadLine());

        Console.Write("Input ha = "); 

        int ha = int.Parse(Console.ReadLine());

        int S = a * ha / 2; 

        Console.WriteLine("Area = "); 

    }

}