Problem:
Handsel

Alice and Brown are brothers in a family and each receives pocket money in celebration of the coming year. They are very close and share the total amount of the money fifty-fifty. The pocket money each receives is a multiple of 1,000 yen.

Write a program to calculate each one’s share given the amount of money Alice and Brown received.

Input

The input is given in the following format.

a b

A line of data is given that contains two values of money: a (1000 ≤ a ≤ 50000) for Alice and b (1000 ≤ b ≤ 50000) for Brown.

Output

Output the amount of money each of Alice and Brown receive in a line.

Sample Input 1

1000 3000

Sample Output 1

2000

Sample Input 2

5000 5000

Sample Output 2

5000

Sample Input 3

1000 2000

Sample Output 3

1500

Solution in C# (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace OthloKyopro
{
    class Program
    {
        static void Main(string[] args)
        {
            /* 101*/
            var a = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToList();
            var sum = 0;
            foreach(var i in a)
            {
                sum += i;
            }
            Console.WriteLine(sum / a.Count());


        }
    }
}