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# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using System.Linq;
namespace Sample
{
  class Sample
  {
    static void Main(string[] args)
    {
    string[] str=Console.ReadLine().Split(' ');
      int A=int.Parse(str[0]);
      int B=int.Parse(str[1]);
      int ans=0;
      for(int i=1;i<=2;i++){
       if(A>=B){
         ans+=A;
         A=A-1;
      }else{
         ans+=B;
         B=B-1;
       }
      }
      Console.WriteLine(ans);
    }
    
  }

}