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 (Clang 3.8.0) (judge verdict: Accepted)

#include<stdio.h>
int max(int a,int b){
  if(a > b)return a;
  return b;
}

int main(void){
  int a,b;
  scanf("%d %d",&a,&b);
  if(a == b){
    printf("%d", 2 * a);
  }else{
    printf("%d",2 * max(a,b) - 1);
  }
  return 0;
}