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Time Limit: 2 s Memory Limit: 512 MB Total points: 100

#10931. 对合排列

统计

我们称一个排列 $p$ 为对合排列当且仅当对于每个 $i$ 有 $p(p(i))=i$。

对于一个给定的正整数 $k$,你需要对于每个 $u\in [0,k]$ 求出:

  • 所有长度为 $n$ 的对合排列中,逆序对个数 $=u$ 的排列个数 mod 2

输入格式

一行两个整数,$n,k$。

输出格式

一行一个长度为 $n$ 的01串,表示每个 $u\in [0,k]$ 的输出。

样例数据

样例输入

3 9

样例输出

1001000000

子任务

对于 $100\%$ 的数据,$1 \leq k, n \leq 10^6$

测试点 $n \leq$ $k \leq $
$1 \sim 2$ $10$ $50$
$3 \sim 4$ $20$ $200$
$5 \sim 7$ $2\,000$ $2 \times 10^5$
$8$ $5 \times 10^5$
$9\sim 10$ $10^6$
$11 \sim 14$ $10^6$ $5 \times 10^4$
$15 \sim 20$ $10^6$

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