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Problem Statement
Chef has a undirected graph G. This graph consists of N vertices and M edges. Each vertex of the graph has an unique index from 1 to N, also each edge of the graph has an unique index from 1 to M.
Also Chef has Q pairs of integers: Li, Ri (1 ≤ Li ≤ Ri ≤ M). For each pair Li, Ri, Chef wants to know: how many connected components will contain graph G if Chef erase all the edges from the graph, except the edges with indies X, where Li ≤ X ≤ Ri. Please, help Chef with these queries.
Input
The first line of the input contains an integer T denoting the number of test cases. The description of T test cases follows.
The first line of each test case contains three integers N, M, Q. Each of the next M lines contains a pair of integers Vi, Ui - the current edge of graph G. Each of the next Q lines contains a pair of integers Li, Ri - the current query.
Output
For each query of each test case print the required number of connected components.
Constraints
- 1 ≤ T ≤ 1000.
- 1 ≤ N, M, Q ≤ 200000.
- 1 ≤ Ui, Vi ≤ N.
- 1 ≤ Li ≤ Ri ≤ M.
- Sum of all values of N for test cases is not greater than 200000. Sum of all values of M for test cases is not greater than 200000. Sum of all values of Q for test cases is not greater than 200000.
- Graph G can contain self-loops and multiple edges.
Example
Input: 2 3 5 4 1 3 1 2 2 1 3 2 2 2 2 3 1 5 5 5 1 2 1 1 1 1 1 1 1 Output: 2 1 3 1 1
破题坑了一晚上
题目大意？见上面超链接的中文题面。
树 LCT 动态维护生成树
将所有询问按右端点递增顺序排序，从1到m依次加边。
用LCT维护当前的生成树，生成树中保留的是编号尽量大的边。
同时用线段树维护生成树中保留了哪些边（权值线段树，存编号）。
查询时，在线段树上查询$[L,R]$范围内有多少条边，若查询结果为$ x $，则连通块数为$n-x$
注意有自环和重边，这使得维护生成树的时候不能一律删编号最靠前的边，而要先查询生成树中有没有重边。
细节蛮多的。
代码太丑，改天优化一下再放