Description
You are given some binary trees of total N vertices numbered from 1 to N.
And M branches connect those trees.
There are Q questions.
Print every direction if you want to walk from node A to node B (Guaranteed only one path if it can be reached),
or "oops" if you can't walk there.
P: move to parent
R: move to right child
L: move to left child
B: move to branch
Limit:
Testcases 1~2: only one tree, M = 0.
Testcase 3: no more than two trees.
Testcases 4~5: N, M <= 3000.
Input
The first line contains two integers N, M (2≤N, M≤3000).
Each of the next N lines contains 2 integers, representing the left child and the right child of the i th node. (and 0 means empty)
Each of the next M lines contains 2 intergers Bi, Bj, representing there is a branch between the Bi node and the Bj node.
The next line contains an integer Q (1≤Q≤3000).
Each of the next Q lines contains two integers, A, B.
Output
For each question, output every direction that walks from node A to node B, or "oops" if you can't walk there.
Remember to add a new line in the end of each question.