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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
int main()
{
    int num;
    // 整数の入力
    scanf("%d", &num);
    
    int heights[20];
    int ans[20];
    // 
    for(int i = 0; i < num; i ++) {
        scanf("%d", &heights[i]);
    }
    // 判定
    int j = 0;
    for(int i = 2; i < num; i ++) {
        int t = heights[i];
        if(t >= heights[0] && t >= heights[1]) {
            if(t >= heights[i-1]) {
                ans[j] = t;
                j++;
            }
        }
    }
    // 出力
    printf("%d¥n", j+1);
    return 0;
}