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 main(){
	
	int A,B,coin=0;
	scanf("%d",&A);
	scanf("%d",&B);
	
	if(A+(A-1)>A+B&&A+(A-1)>B+(B-1)){
	
	coin=2*A-1;
	}else if(2*B-1>2*A-1&&2*B-1>A+B){
		coin=2*B-1;
		
		
	}else {
		coin=A+B;
		
	}
	
	printf("\n%d\n\n",coin);
	
	return 0;
}