307591: CF1379E. Inverse Genealogy

Memory Limit:512 MB Time Limit:1 S
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Description

Inverse Genealogy

题意翻译

给定参数$n,k$($1\le n \le 10^5 ,0\le k \le n$),构造一棵二叉树,满足: - 该二叉树有$n$个节点。 - 不存在只有1个儿子的节点。 - 对于一个非叶子节点,记他的两个儿子对应子树的大小为$A,B$。如果$2A\le B$或者$2B \le A$,那么这个点是“不平衡点”。你构造的二叉树需要**恰好有$k$个“不平衡点”**。 如果无解,输出一行`NO`;否则输出一行`YES`,并在下一行输出每个节点的父亲编号(根节点输出0)表示你的构造。

题目描述

Ivan is fond of genealogy. Currently he is studying a particular genealogical structure, which consists of some people. In this structure every person has either both parents specified, or none. Additionally, each person has exactly one child, except for one special person, who does not have any children. The people in this structure are conveniently numbered from $ 1 $ to $ n $ , and $ s_i $ denotes the child of the person $ i $ (and $ s_i = 0 $ for exactly one person who does not have any children). We say that $ a $ is an ancestor of $ b $ if either $ a = b $ , or $ a $ has a child, who is an ancestor of $ b $ . That is $ a $ is an ancestor for $ a $ , $ s_a $ , $ s_{s_a} $ , etc. We say that person $ i $ is imbalanced in case this person has both parents specified, and the total number of ancestors of one of the parents is at least double the other. Ivan counted the number of imbalanced people in the structure, and got $ k $ people in total. However, he is not sure whether he computed it correctly, and would like to check if there is at least one construction with $ n $ people that have $ k $ imbalanced people in total. Please help him to find one such construction, or determine if it does not exist.

输入输出格式

输入格式


The input contains two integers $ n $ and $ k $ ( $ 1 \leq n \leq 100\,000 $ , $ 0 \leq k \leq n $ ), the total number of people and the number of imbalanced people.

输出格式


If there are no constructions with $ n $ people and $ k $ imbalanced people, output NO. Otherwise output YES on the first line, and then $ n $ integers $ s_1, s_2, \ldots, s_n $ ( $ 0 \leq s_i \leq n $ ), which describes the construction and specify the child of each node (or 0, if the person does not have any children).

输入输出样例

输入样例 #1

3 0

输出样例 #1

YES
0 1 1

输入样例 #2

5 1

输出样例 #2

YES
0 1 1 3 3

输入样例 #3

3 2

输出样例 #3

NO

说明

In the first example case one can have a construction with 3 people, where 1 person has 2 parents. In the second example case one can use the following construction: ![](https://cdn.luogu.com.cn/upload/vjudge_pic/CF1379E/56ef807b09159148574a73651e0ad3983f5cacfe.png)Only person 1 is imbalanced, because one of their parents has 1 ancestor in total, and the other parent has 3 ancestors.

Input

题意翻译

给定参数$n,k$($1\le n \le 10^5 ,0\le k \le n$),构造一棵二叉树,满足: - 该二叉树有$n$个节点。 - 不存在只有1个儿子的节点。 - 对于一个非叶子节点,记他的两个儿子对应子树的大小为$A,B$。如果$2A\le B$或者$2B \le A$,那么这个点是“不平衡点”。你构造的二叉树需要**恰好有$k$个“不平衡点”**。 如果无解,输出一行`NO`;否则输出一行`YES`,并在下一行输出每个节点的父亲编号(根节点输出0)表示你的构造。

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