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 C++ (GCC 9.2.1) (judge verdict: Accepted)

//  ©   ___MRX___

#include <bits/stdc++.h>
    using namespace std;

#define ll long long int

int main()
{
    int a, b, x = 0, i = 0;
    cin >> a >> b;
    while(i < 2) {
        x += max(a, b);
        a > b ? --a : --b;
        i++;
    }

    cout << x << '\n';

    return 0;
}