A8684. Not Wool Sequences
编程题
普及/提高-
知识点
题目描述
A sequence of non-negative integers $a_{1},a_{2},...,a_{n}$ of length $n$ is called a wool sequence if and only if there exists two integers $l$ and $r$ $(1<=l<=r<=n)$ such that . In other words each wool sequence contains a subsequence of consecutive elements with xor equal to 0.
The expression  means applying the operation of a bitwise xor to numbers $x$ and $y$ . The given operation exists in all modern programming languages, for example, in languages C++ and Java it is marked as "^", in Pascal — as "xor".
In this problem you are asked to compute the number of sequences made of $n$ integers from 0 to $2^{m}-1$ that are not a wool sequence. You should print this number modulo $1000000009$ $(10^{9}+9)$ .
The expression  means applying the operation of a bitwise xor to numbers $x$ and $y$ . The given operation exists in all modern programming languages, for example, in languages C++ and Java it is marked as "^", in Pascal — as "xor".
In this problem you are asked to compute the number of sequences made of $n$ integers from 0 to $2^{m}-1$ that are not a wool sequence. You should print this number modulo $1000000009$ $(10^{9}+9)$ .
输入格式
The only line of input contains two space-separated integers $n$ and $m$ $(1<=n,m<=10^{5})$ .
输出格式
Print the required number of sequences modulo $1000000009$ $(10^{9}+9)$ on the only line of output.
输入输出样例
输入 #1
3 2
输出 #1
6
说明/提示
Sequences of length $3$ made of integers 0, 1, 2 and 3 that are not a wool sequence are (1, 3, 1), (1, 2, 1), (2, 1, 2), (2, 3, 2), (3, 1, 3) and (3, 2, 3).