CF1575I.Illusions of the Desert
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题目描述
Chanek Jones is back, helping his long-lost relative Indiana Jones, to find a secret treasure in a maze buried below a desert full of illusions.
The map of the labyrinth forms a tree with n rooms numbered from 1 to n and n−1 tunnels connecting them such that it is possible to travel between each pair of rooms through several tunnels.
The i -th room ( 1≤i≤n ) has ai illusion rate. To go from the x -th room to the y -th room, there must exist a tunnel between x and y , and it takes max(∣ax+ay∣,∣ax−ay∣) energy. ∣z∣ denotes the absolute value of z .
To prevent grave robbers, the maze can change the illusion rate of any room in it. Chanek and Indiana would ask q queries.
There are two types of queries to be done:
- 1 u c — The illusion rate of the x -th room is changed to c ( 1≤u≤n , 0≤∣c∣≤109 ).
- 2 u v — Chanek and Indiana ask you the minimum sum of energy needed to take the secret treasure at room v if they are initially at room u ( 1≤u,v≤n ).
Help them, so you can get a portion of the treasure!
输入格式
The first line contains two integers n and q ( 2≤n≤105 , 1≤q≤105 ) — the number of rooms in the maze and the number of queries.
The second line contains n integers a1,a2,…,an ( 0≤∣ai∣≤109 ) — inital illusion rate of each room.
The i -th of the next n−1 lines contains two integers si and ti ( 1≤si,ti≤n ), meaning there is a tunnel connecting si -th room and ti -th room. The given edges form a tree.
The next q lines contain the query as described. The given queries are valid.
输出格式
For each type 2 query, output a line containing an integer — the minimum sum of energy needed for Chanek and Indiana to take the secret treasure.
输入输出样例
输入#1
6 4 10 -9 2 -1 4 -6 1 5 5 4 5 6 6 2 6 3 2 1 2 1 1 -3 2 1 2 2 3 3
输出#1
39 32 0
说明/提示
In the first query, their movement from the 1 -st to the 2 -nd room is as follows.
- 1→5 — takes max(∣10+4∣,∣10−4∣)=14 energy.
- 5→6 — takes max(∣4+(−6)∣,∣4−(−6)∣)=10 energy.
- 6→2 — takes max(∣−6+(−9)∣,∣−6−(−9)∣)=15 energy.
In total, it takes 39 energy.In the second query, the illusion rate of the 1 -st room changes from 10 to −3 .
In the third query, their movement from the 1 -st to the 2 -nd room is as follows.
- 1→5 — takes max(∣−3+4∣,∣−3−4∣)=7 energy.
- 5→6 — takes max(∣4+(−6)∣,∣4−(−6)∣)=10 energy.
- 6→2 — takes max(∣−6+(−9)∣,∣−6−(−9)∣)=15 energy.
Now, it takes 32 energy.