Triangle on the tree to solve re Runtime Error

Time limit: 4000ms

Single Point time: 2000ms

Memory Limit: 256MB

Describe

There is a tree, there is a caterpillar in the tree. It has lived in this tree for a long time and knows its structure well. So it has always been the shortest way in the tree, will not go a detour. It also loves triangles especially, so when it crawls up and down the tree, it always thinks, if you saw the branches/trunks that had just climbed, could you choose three from them to spell a triangle?

Input

The first row of the input data contains an integer T that represents the number of data groups.
Next there is the T-group data, each set of data:
The first row contains an integer N that represents the number of nodes (from 1 to N) on the tree.
The next N-1 line contains three integers a, B, Len, which indicates that there is a branch/trunk length of Len between Node A and Node B.
The next line contains an integer M representing the number of inquiries.
The next m line is two integers per line s, T, which means the caterpillar crawls from S to T, asking if the branches/trunks in the distance can be spelled into triangles.

1≤t≤5
Small data: 1≤n≤100, 1≤m≤100, 1≤len≤10000
Big data: 1≤n≤100000,1≤m≤100000, 1≤len≤1000000000

Output

For each set of data, first output a line of "case#x:" Where X is the number of data sets, starting at 1.
Next, for each query output row, contains "Yes" or "No" to indicate whether a triangle can be spelled.

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Sample input

2

5

1 2 5

1 3 20

2 4 30

4 5 15

2

3 4

3 5

5

1 4 32

2 3 100

3 5 45

4 5 60

2

1 4

1 3

Sample output

Case #1:

No

Yes

Case #2:

No

Yes

This problem was done yesterday always reported re, that is, run-time error runtime errors, because it is the test system does not allow the creation of multiple classes, even if the internal class is not, the way is to rewrite the form of the number of groups.

Add: It's OK to create multiple classes, this can't be a heap overflow or any other problem, hopefully not to mislead everyone. The end result is tle, still need to improve.

Ideas:

1, read the data, build the diagram

2, breadth first traversal, find the destination point. This process is definitely the shortest way, because this is a tree, two points between only one path (without duplication). In the traversal process, save the parent node of each point traversal, so that you can know which nodes have gone through.

3, traversing any of the three edges of the combination can be composed of triangles.

I created some test data myself and felt that large data should also be available and not timed out. Only the last step seems to be less efficient, in fact, some articles say that when the number of sides more than 50 o'clock, must be able to form a triangle, so in fact it does not traverse so many times to return.