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 JavaScript (node.js v5.12) (judge verdict: Accepted)

"use strict";
function Main(input) {
    let lines = input.split("\n");
    let ab = lines.shift().split(/\s/).map((v) => v - 0);
    let A = ab[0], B = ab[1];
    let set = [[A, A-1], [A, B], [B, B-1]];
    let sum = set.map((v) => v[0] + v[1]);
    let ans = Math.max(...sum);
    console.log(ans);
}
if (typeof window == "undefined") Main(require("fs").readFileSync("/dev/stdin", "utf8"));