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() {
  /* code */
  int n, i, maxh = 0, can_see = 1, h;
  scanf("%d\n", &n);
  scanf("%d", &h);
  maxh = h;
  for (i = 0; i < n - 1; i++) {
    /* code */
    scanf(" %d\n", &h);
    if (maxh < h) {
      /* code */
      maxh = h;
      can_see++;
    }
  }
  printf("%d\n", can_see);
  return 0;
}