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;
using System.Collections.Generic;

    class Program
    {
        static void Main(string[] args)
        {
            var input = Console.ReadLine();
            string[] strinputArray = input.Split(' ');
            int[] intinputArray = Array.ConvertAll<string, int>(strinputArray, delegate (string value) { return int.Parse(value); });
            
            if(intinputArray[0] > intinputArray[1])
            {
                if(intinputArray[0] - 1 > intinputArray[1])
                {
                    Console.WriteLine(intinputArray[0] + intinputArray[0] - 1);
                }
                else
                {
                    Console.WriteLine(intinputArray[0] + intinputArray[1]);
                }
            }
            else
            {
                if (intinputArray[0] < intinputArray[1] - 1)
                {
                    Console.WriteLine(intinputArray[1] + intinputArray[1] - 1);
                }
                else
                {
                    Console.WriteLine(intinputArray[0] + intinputArray[1]);
                }
            }
            Console.ReadLine();
        }
    }