CF1296F.Berland Beauty

普及/提高-

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题目描述

There are nn railway stations in Berland. They are connected to each other by n1n-1 railway sections. The railway network is connected, i.e. can be represented as an undirected tree.

You have a map of that network, so for each railway section you know which stations it connects.

Each of the n1n-1 sections has some integer value of the scenery beauty. However, these values are not marked on the map and you don't know them. All these values are from 11 to 10610^6 inclusive.

You asked mm passengers some questions: the jj -th one told you three values:

  • his departure station aja_j ;
  • his arrival station bjb_j ;
  • minimum scenery beauty along the path from aja_j to bjb_j (the train is moving along the shortest path from aja_j to bjb_j ).

You are planning to update the map and set some value fif_i on each railway section — the scenery beauty. The passengers' answers should be consistent with these values.

Print any valid set of values f1,f2,,fn1f_1, f_2, \dots, f_{n-1} , which the passengers' answer is consistent with or report that it doesn't exist.

输入格式

The first line contains a single integer nn ( 2n50002 \le n \le 5000 ) — the number of railway stations in Berland.

The next n1n-1 lines contain descriptions of the railway sections: the ii -th section description is two integers xix_i and yiy_i ( 1xi,yin,xiyi1 \le x_i, y_i \le n, x_i \ne y_i ), where xix_i and yiy_i are the indices of the stations which are connected by the ii -th railway section. All the railway sections are bidirected. Each station can be reached from any other station by the railway.

The next line contains a single integer mm ( 1m50001 \le m \le 5000 ) — the number of passengers which were asked questions. Then mm lines follow, the jj -th line contains three integers aja_j , bjb_j and gjg_j ( 1aj,bjn1 \le a_j, b_j \le n ; ajbja_j \ne b_j ; 1gj1061 \le g_j \le 10^6 ) — the departure station, the arrival station and the minimum scenery beauty along his path.

输出格式

If there is no answer then print a single integer -1.

Otherwise, print n1n-1 integers f1,f2,,fn1f_1, f_2, \dots, f_{n-1} ( 1fi1061 \le f_i \le 10^6 ), where fif_i is some valid scenery beauty along the ii -th railway section.

If there are multiple answers, you can print any of them.

输入输出样例

  • 输入#1

    4
    1 2
    3 2
    3 4
    2
    1 2 5
    1 3 3

    输出#1

    5 3 5
  • 输入#2

    6
    1 2
    1 6
    3 1
    1 5
    4 1
    4
    6 1 3
    3 4 1
    6 5 2
    1 2 5

    输出#2

    5 3 1 2 1
  • 输入#3

    6
    1 2
    1 6
    3 1
    1 5
    4 1
    4
    6 1 1
    3 4 3
    6 5 3
    1 2 4

    输出#3

    -1
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