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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <vector>
#include <map>
#include <list>
#include <math.h>
#include <algorithm>
#include <chrono>
#include <random>
#include <queue>
#include <fstream>
#include <iterator> // std::back_inserter
#include <chrono>
#include <string>
#include <stdio.h>
#include <iomanip>
#include <float.h>
#include <cassert>
#include <functional>

using namespace std;

int main(int argc, char *argv[])
{
    int a, b;
    cin >> a >> b;

    int ans = 0;

    if (a > b)
    {
        ans += a;
        a -= 1;
    }
    else
    {
        ans += b;
        b -= 1;
    }

    if (a > b)
    {
        ans += a;
        a -= 1;
    }
    else
    {
        ans += b;
        b -= 1;
    }

    cout << ans;

    return 0;
}