#P2982. [USACO10FEB] Slowing down G

    ID: 2023 远端评测题 1000ms 125MiB 尝试: 0 已通过: 0 难度: 7 上传者: 标签>2010线段树USACO树状数组深度优先搜索,DFS

[USACO10FEB] Slowing down G

Description

Every day, each of Farmer John's NN (1N100,000)(1 \le N \le 100{,}000) cows, conveniently numbered 1..N1..N, moves from the barn to her private pasture. The pastures form a tree, with the barn at pasture 11. Exactly N1N-1 undirected paths connect the pastures; directly connected pastures have exactly one path. Path ii connects pastures AiA_i and BiB_i (1AiN,1BiN)(1 \le A_i \le N, 1 \le B_i \le N).

Cow ii has a private pasture PiP_i (1PiN)(1 \le P_i \le N). The barn's small door lets only one cow exit at a time, and the patient cows wait until their predecessor arrives at her private pasture. First, cow 11 exits and moves to pasture P1P_1. Then cow 22 exits and goes to pasture P2P_2, and so on.

While cow ii walks to PiP_i, she might or might not pass through a pasture that already contains an eating cow. When a cow is present in a pasture, cow ii walks slower than usual while passing through that pasture to avoid annoying her friend.

Consider the following pasture network, where the number between
parentheses indicates the pastures' owner.

        1 (3)        
       / \
  (1) 4   3 (5)
     / \   
(2) 2   5 (4)

First, cow 1 walks to her pasture:

        1 (3)        
       / \
  [1] 4*  3 (5)
     / \   
(2) 2   5 (4)

When cow 2 moves to her pasture, she first passes into the barn's
pasture, pasture 1. Then she sneaks around cow 1 in pasture 4 before
arriving at her own pasture.

        1 (3)
       / \
  [1] 4*  3 (5)
     / \   
[2] 2*  5 (4)

Cow 3 doesn't get far at all -- she lounges in the barn's pasture, #1.

        1* [3]
       / \
  [1] 4*  3 (5)
     / \   
[2] 2*  5 (4)

Cow 4 must slow for pasture 1 and 4 on her way to pasture 5:

        1* [3]
       / \
  [1] 4*  3 (5)
     / \   
[2] 2*  5* [4]

Cow 5 slows for cow 3 in pasture 1 and then enters her own private pasture:

        1* [3]
       / \
  [1] 4*  3*[5]
     / \   
[2] 2*  5* [4]

FJ would like to know how many times each cow has to slow down.

Input Format

  • Line 1: An integer NN.
  • Lines 2..N2..N: Line i+1i+1 contains two space-separated integers AiA_i and BiB_i.
  • Lines N+1..N+NN+1..N+N: Line N+iN+i contains a single integer PiP_i.

Output Format

  • Lines 1..N1..N: Line ii contains the number of times cow ii has to slow down.
5 
1 4 
5 4 
1 3 
2 4 
4 
2 
1 
5 
3 

0 
1 
0 
2 
1 

Hint

Constraints: 1Ai,Bi,PiN1051 \leq A_i, B_i, P_i \leq N \leq 10^5.

Translated by ChatGPT 5