CF1007D.Ants

普及/提高-

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题目描述

There is a tree with nn vertices. There are also mm ants living on it. Each ant has its own color. The ii -th ant has two favorite pairs of vertices: ( ai,bia_i, b_i ) and ( ci,dic_i, d_i ). You need to tell if it is possible to paint the edges of the tree in mm colors so that every ant will be able to walk between vertices from one of its favorite pairs using only edges of his color; if it is possible, you need to print which pair every ant should use.

输入格式

The first line contains a single integer nn ( 2n1052 \leq n \leq 10^5 ) — the number of vertices.

Each of the next n1n-1 lines contains two integers uiu_i and viv_i ( 1ui,vin1 \leq u_i, v_i \leq n ), meaning that there is an edge between vertices uiu_i and viv_i .

The next line contains a single integer mm ( 1m1041 \leq m \leq 10^4 ) — the number of ants.

Each of the next mm lines contains four integers aia_i , bib_i , cic_i , and did_i ( 1ai,bi,ci,din1 \leq a_i, b_i, c_i, d_i \leq n , aibi,cidia_i \neq b_i, c_i \neq d_i ), meaning that pairs ( aia_i , bib_i ) and ( cic_i , did_i ) are favorite for the ii -th ant.

输出格式

Print "NO" (without quotes) if the wanted painting is impossible.

Otherwise, print "YES" (without quotes). Print mm lines. On the ii -th line, print 11 if the ii -th ant will use the first pair and 22 otherwise. If there are multiple answers, print any.

输入输出样例

  • 输入#1

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

    输出#1

    YES
    2
    1
    2
    
  • 输入#2

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

    输出#2

    NO
    

说明/提示

In the sample, the second and the third edge should be painted in the first color, the first and the fifth should be painted in the second color, and the fourth should be painted in the third color.

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