CF1844G.Tree Weights

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题目描述

You are given a tree with nn nodes labelled 1,2,,n1,2,\dots,n . The ii -th edge connects nodes uiu_i and viv_i and has an unknown positive integer weight wiw_i . To help you figure out these weights, you are also given the distance did_i between the nodes ii and i+1i+1 for all 1in11 \le i \le n-1 (the sum of the weights of the edges on the simple path between the nodes ii and i+1i+1 in the tree).

Find the weight of each edge. If there are multiple solutions, print any of them. If there are no weights wiw_i consistent with the information, print a single integer 1-1 .

输入格式

The first line contains a single integer nn ( 2n1052 \le n \le 10^5 ).

The ii -th of the next n1n-1 lines contains two integers uiu_i and viv_i ( 1ui,vin1 \le u_i,v_i \le n , uiviu_i \ne v_i ).

The last line contains n1n-1 integers d1,,dn1d_1,\dots,d_{n-1} ( 1di10121 \le d_i \le 10^{12} ).

It is guaranteed that the given edges form a tree.

输出格式

If there is no solution, print a single integer 1-1 . Otherwise, output n1n-1 lines containing the weights w1,,wn1w_1,\dots,w_{n-1} .

If there are multiple solutions, print any of them.

输入输出样例

  • 输入#1

    5
    1 2
    1 3
    2 4
    2 5
    31 41 59 26

    输出#1

    31
    10
    18
    8
  • 输入#2

    3
    1 2
    1 3
    18 18

    输出#2

    -1
  • 输入#3

    9
    3 1
    4 1
    5 9
    2 6
    5 3
    5 8
    9 7
    9 2
    236 205 72 125 178 216 214 117

    输出#3

    31
    41
    59
    26
    53
    58
    97
    93

说明/提示

In the first sample, the tree is as follows:

In the second sample, note that w2w_2 is not allowed to be 00 because it must be a positive integer, so there is no solution.

In the third sample, the tree is as follows:

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