QTREE2  Query on a tree II
You are given a tree (an undirected acyclic connected graph) with N nodes, and edges numbered 1, 2, 3...N1. Each edge has an integer value assigned to it, representing its length.
We will ask you to perfrom some instructions of the following form:
 DIST a b : ask for the distance between node a and node b
or  KTH a b k : ask for the kth node on the path from node a to node b
Example:
N = 6
1 2 1 // edge connects node 1 and node 2 has cost 1
2 4 1
2 5 2
1 3 1
3 6 2
Path from node 4 to node 6 is 4 > 2 > 1 > 3 > 6
DIST 4 6 : answer is 5 (1 + 1 + 1 + 2 = 5)
KTH 4 6 4 : answer is 3 (the 4th node on the path from node 4 to node 6 is 3)
Input
The first line of input contains an integer t, the number of test cases (t <= 25). t test cases follow.
For each test case:
 In the first line there is an integer N (N <= 10000)
 In the next N1 lines, the ith line describes the ith edge: a line with three integers a b c denotes an edge between a, b of cost c (c <= 100000)
 The next lines contain instructions "DIST a b" or "KTH a b k"
 The end of each test case is signified by the string "DONE".
There is one blank line between successive tests.
Output
For each "DIST" or "KTH" operation, write one integer representing its result.
Print one blank line after each test.
Example
Input: 1 6 1 2 1 2 4 1 2 5 2 1 3 1 3 6 2 DIST 4 6 KTH 4 6 4 DONE Output: 5 3
hide comments
lamia2658:
20181113 20:16:11
a must do LCA problem after learning 

vaishcr7:
20180801 13:18:40
i am getting nzec error in this , i have tried taking input in many different ways. Is anybody else also facing the same problem ? 

kspoj:
20180520 10:47:38
Guys, I'm using sqrt decomp for finding LCA and am getting WA (at the very first test)


sggutier:
20171209 00:33:46
Are the test cases correct? For some reason, my solution only works when I send it in C++14 with clang.


a_sinkevich:
20171110 11:20:57
Last edit: 20171110 16:30:10 

shishir_hstu:
20170907 20:12:04
easy to solve using LCA with parse tree. also can find KTH parent from parse table. :D 

starbot:
20170907 16:21:53
GOT AC AFTER USING long long.... 

justforpractic:
20170722 23:23:39
when dealing with levels of parents of nodes don't forget to check if parent[node][j] != 1 to avoid Run time error


nitesh_gupta:
20170721 10:21:40
Got segmentation fault in C++(g++4.3.2) but same solution got accepted in C++(gcc 6.3). 

justforpractic:
20170721 02:45:39
Is it sufficient to answer each query in the order of the path from a to b ? 
Added by:  ThanhVy Hua 
Date:  20060827 
Time limit:  0.433s 
Source limit:  15000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: ERL JSRHINO NODEJS PERL6 VB.NET 
Resource:  Special thanks to Ivan Krasilnikov for his alternative solution 