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: Runtime Error)

function Main(input){
  input = input.split("\n"); // 'A B'
  inputStr = input[0].split(" ");
  let a = Number.parseInt(inputStr[0]);
  let b = Number.parseInt(inputStr[1]);
  
  console.log(Math.max(a*2-1,b*2-1,a+b));
  
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));