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A14769. Infinite Set

编程题 普及/提高-

题目描述

You are given an array $a$ consisting of $n$ distinct positive integers.

Let's consider an infinite integer set $S$ which contains all integers $x$ that satisfy at least one of the following conditions:

1. $x = a_i$ for some $1 \leq i \leq n$ .
2. $x = 2y + 1$ and $y$ is in $S$ .
3. $x = 4y$ and $y$ is in $S$ .

For example, if $a = [1,2]$ then the $10$ smallest elements in $S$ will be $\{1,2,3,4,5,7,8,9,11,12\}$ .

Find the number of elements in $S$ that are strictly smaller than $2^p$ . Since this number may be too large, print it modulo $10^9 + 7$ .

输入格式

The first line contains two integers $n$ and $p$ $(1 \leq n, p \leq 2 \cdot 10^5)$ .

The second line contains $n$ integers $a_1,a_2,\ldots,a_n$ $(1 \leq a_i \leq 10^9)$ .

It is guaranteed that all the numbers in $a$ are distinct.

输出格式

Print a single integer, the number of elements in $S$ that are strictly smaller than $2^p$ . Remember to print it modulo $10^9 + 7$ .

输入输出样例

输入 #1
2 4
6 1
输出 #1
9
输入 #2
4 7
20 39 5 200
输出 #2
14
输入 #3
2 200000
48763 1000000000
输出 #3
448201910

说明/提示

In the first example, the elements smaller than $2^4$ are $\{1, 3, 4, 6, 7, 9, 12, 13, 15\}$ .

In the second example, the elements smaller than $2^7$ are $\{5,11,20,23,39,41,44,47,79,80,83,89,92,95\}$ .
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