第 231 场 AtCoder Regular Contest
F
两棵不平衡子树
Two Unbalanced Subtrees
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原题
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两棵不平衡子树AI (CI翻译)

Problem Statement

题目描述

AI (CI翻译)

You are given a positive integer $N$.

给定一个正整数 $N$。AI (CI翻译)

There is a perfect binary tree with $2^N - 1$ vertices. The vertices are numbered from $1$ to $2^N - 1$.

有一棵包含 $2^N - 1$ 个顶点的完美二叉树。顶点编号为 $1$ 到 $2^N - 1$。AI (CI翻译)

Vertex $1$ is the root, and for each vertex $i$ ($1 \leq i < 2^{N - 1}$), vertex $i$ has vertex $2i$ and vertex $2i + 1$ as its children.

顶点 $1$ 是根。对于每个顶点 $i$($1 \leq i < 2^{N - 1}$),顶点 $i$ 的子节点为顶点 $2i$ 和顶点 $2i + 1$。AI (CI翻译)

Among the ways to write an integer between $1$ and $2^N - 1$, inclusive, on each vertex (where the $2^N - 1$ written integers must be pairwise distinct) such that the following condition is satisfied, find one that minimizes the integer written on vertex $1$.

现在考虑在每个顶点上写入一个介于 $1$ 和 $2^N - 1$(含)之间的整数,且写入的 $2^N - 1$ 个整数必须两两不同,并满足以下条件。在所有满足条件的写法中,找出一种使顶点 $1$ 上写入的整数最小的方案。AI (CI翻译)

  • For each vertex $i$ ($1 \leq i < 2^{N - 1}$), the integer written on vertex $i$ is the absolute difference between the sum of the integers written on the vertices of the subtree rooted at vertex $2i$ and the sum of the integers written on the vertices of the subtree rooted at vertex $2i+1$.
  • 对于每个顶点 $i$($1 \leq i < 2^{N - 1}$),顶点 $i$ 上写入的整数等于以顶点 $2i$ 为根的子树中各顶点上写入的整数之和,与以顶点 $2i+1$ 为根的子树中各顶点上写入的整数之和,这两个和的绝对差。
AI (CI翻译)

It can be proved that, under the constraints of this problem, a way of writing integers satisfying the condition always exists.

可以证明,在本题的约束条件下,满足条件的写法总是存在。AI (CI翻译)

Constraints

约束条件

AI (CI翻译)
  • $2 \leq N \leq 18$
  • All input values are integers.
  • $2 \leq N \leq 18$
  • 所有输入值均为整数。
AI (CI翻译)

Input

输入格式

AI (CI翻译)

The input is given from Standard Input in the following format:

输入从标准输入按以下格式给出:AI (CI翻译)

N

N
AI (CI翻译)

Output

输出格式

AI (CI翻译)

Let $P_i$ be the integer written on vertex $i$ ($1 \leq i \leq 2^N - 1$), and output in the following format:

令 $P_i$ 表示顶点 $i$ 上写入的整数($1 \leq i \leq 2^N - 1$),请按以下格式输出:AI (CI翻译)

P_1 P_2 \cdots P_{2^N - 1}

P_1 P_2 \cdots P_{2^N - 1}
AI (CI翻译)

$(P_1, P_2, \cdots, P_{2^N - 1})$ must be a permutation of $(1, 2, \cdots, 2^N - 1)$. If there are multiple ways of writing satisfying the condition that minimize the integer written on vertex $1$, any of them will be considered correct.

$(P_1, P_2, \cdots, P_{2^N - 1})$ 必须是 $(1, 2, \cdots, 2^N - 1)$ 的一个排列。如果有多种满足条件且能使顶点 $1$ 上写入的整数最小的写法,输出其中任意一种均可。AI (CI翻译)

样例

Input #1
2
Output #1
1 2 3
It can be verified as follows that this way of writing satisfies the condition. Also, the integer written on vertex $1$ is clearly minimized. - $i = 1$: The sum of the integers written on the vertices of the subtree rooted at vertex $2$ is $2$, the sum of the integers written on the vertices of the subtree rooted at vertex $3$ is $3$, and $∣2 − 3∣ = 1$. The way of writing $2, 3, 1$ on vertices $1, 2, 3$, respectively, satisfies the condition, but the integer written on vertex $1$ is not the minimum, so it will be judged as incorrect.
题目信息
题号
arc231_f
时间限制
2 s
内存限制
1024 MB

题面与样例版权归 AtCoder 及出题人所有;中文翻译由 AI 生成(gpt-6.1-sol),如有出入请以原文为准。