Simple XOR Problem

Problem Description

Consider the set of integers $\lbrace 0, 1, 2, \ldots, 2^m - 1 \rbrace$. Choose $k$ numbers from it so that their XOR sum equals $n$. Output the largest possible $k$.

Input Format

Two numbers $n$ and $m$, where $0 \leq n \leq 2^m - 1$ and $1 \leq m \leq 60$.

Output Format

Output the largest possible $k$.

Sample Input

2 2

Sample Output

3

Sample Explanation

For the sample, we can choose $\lbrace 0, 1, 3 \rbrace$, whose XOR sum is $2$.