TREEORD - Tree _order

Description

A tree is a connected acyclic graph.
A binary tree is a tree for which each node has a left child, a right child, both, or neither, e.g.
    1
   / \
  2   3
 / \   \
4   5   6
There are three common ways to recursively traverse such a tree.
  1. Pre-order: parent, left subtree, right subtree
  2. Post-order: left subtree, right subtree, parent
  3. In-order: left subtree, parent, right subtree
Given pre-order, post-order, and in-order traversals, determine if they can be of the same binary tree.
For example,
1 2 4 5 3 6
4 5 2 6 3 1
4 2 5 1 3 6
are the pre-order, post-order, and in-order traversals of the tree above.
But
1 2 4 5 3 6
4 5 2 6 1 3
4 2 5 1 6 3
cannot be the pre-order, post-order, and in-order traversals of the same binary tree.

Input

The first line is the number of nodes in each traversal, 0 < N <= 8000.
The second line is the N space separated nodes of the pre-order traversal.
The third line is the N space separated nodes of the post-order traversal.
The fourth line is the N space separated nodes of the in-order traversal.
Each traversal is a sequence of the nodes, numbered 1 to N, without repetition.

Output

Print "yes" if all three traversals can be of the same tree, and "no" otherwise.
Input Input
6
1 2 4 5 3 6
4 5 2 6 3 1
4 2 5 1 3 6
6
1 2 4 5 3 6
4 5 2 6 1 3
4 2 5 1 6 3
Output Output
yes
no

Added by:BYU Admin
Date:2014-02-23
Time limit:0.5s-3s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64

hide comments
2020-05-13 20:41:37
AC in the first go. Try using a map for making use to inorder and postorder traversal to generate the expected pre-order traversal and comparing it with the given pre-order.

Last edit: 2020-06-19 08:47:35
2020-03-10 23:33:48
Very interesting problem!!!
2019-08-22 14:34:56
@saltyfish233 how
2018-12-05 04:50:50
Its embarrasing but I did 4 WA because I was printing 'Yes' instead of 'yes'.
2018-06-28 12:40:29
can anyone help in solving this problem without building tree .

Email Id : shivi98g@gmail.com
2018-05-03 16:04:48
Solved by Tree Construction
2017-11-19 13:21:16
I don`t use recursion but I use stack to solve it :D
2017-11-11 18:05:40
Wow..This.Is.Cool
Learnt some.... :0 :D
2017-03-31 11:37:21 Pranv Gupta
nice question, but wondering if there is only ONE testcase of this problem
2016-10-22 23:43:56 deerishi
MY 100th! 0.00 sec.!! Funny thing : With and without Tree construction with Fast IO accepted in 0.00s !! Without tree construction is cooler though.

Last edit: 2016-10-23 00:57:34
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