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 Java8 (OpenJDK 1.8.0) (judge verdict: Runtime Error)

import java.util.Scanner;
 
public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String input = sc.nextLine();
		int countA = 0;
		int countB = 0;
		int A =0;
		int B =1;
		for (int i = 0; i < input.length() ; i++) {
			int tmp = combertInt(input,i);
			if(A == tmp) {
            	countA++;
            }
          	if(A==0) {
				A=1;
			}else{
				A=0;
			}
          	if(B == tmp) {
            	countB++;
            }
			if(B==1) {
				B=0;
			}else{
				B=1;
			}
		}
		System.out.println(Math.min(countA, countB));
	}
	
	private static Integer combertInt(String s, int i) {
		return Integer.parseInt(s.substring(i,i+1));
	}
}