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 Scala (2.11.7) (judge verdict: Accepted)

object Main {
  def main(args: Array[String]): Unit = {
    var button_size = io.StdIn.readLine().split(" ").map{_.toInt}
    var total_coin  = 0

    (0 until 2).foreach { i =>
      if(button_size(0) > button_size(1)) {
        total_coin += button_size(0)
        button_size(0) -= 1
      }
      else {
        total_coin += button_size(1)
        button_size(1) -= 1
      }
    }
    println(total_coin)
  }
}