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: Wrong Answer)

#include <iostream>
#include <string>
using namespace std;

int main(void) {
	unsigned short a=0, b=0;
	cin >> a >> b;
	unsigned buf[3] = { 0 };
	buf[0] = a + (a-1);
	buf[1] = b + (b-1);
	buf[2] = a + b;
	auto bi = (buf[0] < buf[1]) ? ((buf[1] < buf[2]) ? buf[1] : buf[2] ): buf[0];
	cout << bi << endl;
	return 0;
}