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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
class Pg{
  static void Main(string[] args){
    string[] x = Console.ReadLine().Split();
    int bx = int.Parse(x[0]);
    int by = int.Parse(x[1]);
    int coin = 0;
    for(int i = 0;i < 2;i++){
      if(bx > by){
        coin += bx;
        bx--;
      }else{
        coin += by;
        by--;
      }
    }
    Console.WriteLine(coin);
  }
}