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: Accepted)

#include<stdio.h>

int max(int a,int b);

int main(void)
{
	int a,b,sum=0,k=0;
	scanf("%d%d",&a,&b);
	k = max(a,b);

	sum = sum + k;

	if(k == a) a = a - 1;
	else if(k == b) b = b - 1;
	
	sum = sum + max(a,b);
	printf("%d",sum);
	return 0;
}

int max(int a,int b)
{
	if(a >= b)
	{
		return a;
	}
	else
	{
		return b; 
	}
}