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 PHP7 (7.0.15) (judge verdict: Wrong Answer)

#!/usr/bin/env php
<?
function solve(int $a, int $b)
{
    if ($a == $b) {
        echo $a * 2;
    } elseif ($a > $b) {
        echo $a * 2 - 1;
    } else {
        echo $b * 2 - 1;
    }
    echo PHP_EOL;
}

fscanf(STDIN, '%d %d', $a, $b);
solve($a, $b);