Problem:
Score : 100 points

Problem Statement

There are two buttons, one of size A and one of size B.

When you press a button of size X, you get X coins and the size of that button decreases by 1.

You will press a button twice. Here, you can press the same button twice, or press both buttons once.

At most how many coins can you get?

Constraints

All values in input are integers.

3 \leq A, B \leq 20

Input

Input is given from Standard Input in the following format:

A B

Output

Print the maximum number of coins you can get.

Sample Input 1

5 3

Sample Output 1

9

You can get 5 + 4 = 9 coins by pressing the button of size 5 twice, and this is the maximum result.

Sample Input 2

3 4

Sample Output 2

7

Sample Input 3

6 6

Sample Output 3

12

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

using System;

class Program
{
  static void Main(string[] args)
  {
    Console.ReadLine();
    var cmps = Console.ReadLine().Split(' ');
    int maxHeight = int.MinValue;
    int total = 0;
    for (int i = 0; i < cmps.Length; ++i) {
      var h = int.Parse(cmps[i]);
      if (h >= maxHeight) {
        total++;
      }
      maxHeight = Math.Max(maxHeight, h);
    }
    Console.WriteLine(total);
  }
}