Good Bye 2021: 2022 is NEAR
H
Keep XOR Low
Codeforces
3000
原题
← G→
翻译中…

You are given an array $a_1, a_2, \ldots, a_n$ and an integer $x$.

翻译中…

Find the number of non-empty subsets of indices of this array $1 \leq b_1 \lt b_2 \lt \ldots \lt b_k \leq n$, such that for all pairs $(i, j)$ where $1 \leq i \lt j \leq k$, the inequality $a_{b_i} \oplus a_{b_j} \leq x$ is held. Here, $\oplus$ denotes the bitwise XOR operation. As the answer may be very large, output it modulo $998\,244\,353$.

翻译中…

Input

翻译中…

The first line of the input contains two integers $n$ and $x$ ($1 \leq n \leq 150\,000$, $0 \leq x \lt 2^{30}$). Here, $n$ is the size of the array.

翻译中…

The next line contains $n$ integers $a_1, a_2, \ldots, a_n$ ($0 \leq a_i \lt 2^{30}$): the array itself.

翻译中…

Output

翻译中…

Print one integer: the number of non-empty subsets such that the bitwise XOR of every pair of elements is at most $x$, modulo $998\,244\,353$.

翻译中…

样例

Input #1
4 2
0 1 2 3
Output #1
8
InputCopy OutputCopy
Input #2
3 6
4 2 2
Output #2
7
InputCopy OutputCopy
Input #3
4 0
1 1 2 2
Output #3
6
InputCopy OutputCopy
题目信息
题号
1616H
时间限制
1 s
内存限制
256 MB
标签
位运算
组合数学
数据结构
分治
动态规划
数学

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