Problem:
Score: 100 points

Problem Statement

There is a train going from Station A to Station B that costs X yen (the currency of Japan).

Also, there is a bus going from Station B to Station C that costs Y yen.

Joisino got a special ticket. With this ticket, she can take the bus for half the fare if she travels from Station A to Station B by train and then travels from Station B to Station C by bus.

How much does it cost to travel from Station A to Station C if she uses this ticket?

Constraints

1 \leq X,Y \leq 100

Y is an even number.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

X Y

Output

If it costs x yen to travel from Station A to Station C, print x.

Sample Input 1

81 58

Sample Output 1

110

The train fare is 81 yen.

The train fare is 58 ⁄ 2=29 yen with the 50% discount.

Thus, it costs 110 yen to travel from Station A to Station C.

Sample Input 2

4 54

Sample Output 2

31

Solution in C# (Mono 4.6.2.0) (judge verdict: Runtime Error)

using System;
using System.Linq;
using System.Collections.Generic;
public class P {
    public static void Main() {
        var s = Console.ReadLine().Split(' ');
        int N = int.Parse(s[0]), M = int.Parse(s[1]);
        //int p, y;
        List<int>[] vs = new List<int>[N];
        for(int i=0;i<N;i++)vs[i]=new List<int>();
        List<long> al = new List<long>();
        for (int i = 0;i<M;i++){
            s=Console.ReadLine().Split(' ');
            vs[int.Parse(s[0])-1].Add(int.Parse(s[1]));
            al.Add(100000*(int.Parse(s[0])-1)+int.Parse(s[1]));//あとで探索とかする
        }
        foreach (List<int> ts in vs) {
            ts.Sort();
        }
        for (int i = 0;i<M;i++){
        	long Ind = al[i]/100000;
            for (int f = 0;f<vs[Ind].Sum(x => 1);f++){
                int[] a = vs[Ind].ToArray();
                if (a[f]==(int)(al[i]-(long)100000*Ind)) Console.WriteLine((Ind+1).ToString().PadLeft(6,'0')+(f+1).ToString().PadLeft(6,'0'));
            }
        }
 
    }
}