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>
#include<stdlib.h>
#include<string.h>
#include<math.h>

/*int intsort(const void *a, const void *b){
	return *(int*)a - *(int*)b;
	/*qsort(a,aの配列数,sizeof(int),intsort);*/
/*}

int longsort(const void *a, const void *b){
	long *A=(long *)a;
	long *B=(long *)b;
	if(*A>*B) return -1;
	if(*A<*B) return 1;
	return 0;
}*/

int main(){
	int N,M;
	scanf("%d",&N);
	scanf("%d",&M);

	if(N==M){
		printf("%d",N*2);
	}else if(N>M){
		printf("%d",N*2-1);
	}else{
		printf("%d",M*2-1);
	}
	return 0;
}