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;
using System.Collections.Generic;

namespace ABC124 {
  class ProblemA {
    static void Main(string[] args) {
      int[] nums = Input.nums;
      int a = nums[0], b = nums[1];

      int ans = 0;
      if (a > b) {
        ans += a;
        a--;
      } else {
        ans += b;
        b--;
      }

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

      System.Console.WriteLine(ans);
    }
  }
  public class Input {
    public static string str => System.Console.ReadLine();
    public static string[] strs => str.Split(' ');
    public static char[] charArr => str.ToCharArray();
    public static int num => int.Parse(str);
    public static int[] nums => Array.ConvertAll(strs, int.Parse);
    public static long numL => long.Parse(str);
    public static long[] numLs => Array.ConvertAll(strs, long.Parse);
  }
}