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: Accepted)

<?php
$input = explode(' ', trim(fgets(STDIN)));

$a = (int)$input[0];
$b = (int)$input[1];

$max = max($a,$b);
if ($max === $a) {
	$max2 = max($max-1, $b);
}else{
	$max2 = max($max-1, $a);
}
echo $max + $max2;