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(void)
{
   int  a,b,c;
   scanf("%d%d",&a,&b);                                              
   if((b<a-1)&&(3<=a)&&(3<=b)&&(20>=a)&&(20>=b)){
             c=a+a-1;
             printf("%d\n",c);}
   else if((b>=a-1)&&(3<=a)&&(3<=b)&&(20>=a)&&(20>=b)){
                   c=a+b;
                   printf("%d\n",c);}
   return 0;
}