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 A,B,sum=0,i;
  
  scanf("%d %d", &A, &B);
  if(A<3 || B>20){
    scanf("%d %d", &A, &B);
  }
  
  for(i=0;i++;i<=1){
    if(A>=B){
      sum = sum + A;
      A = A -1;
    }else{
      sum = sum + B;
      B = B -1;
    }
  }
  
  printf("%d",sum);
  
  return 0;
  
}