P15049 [UOI 2022 II Stage] Graph 2
Background
Double experience: .
Description
You are given a graph with $n$ vertices. You are also given $q$ queries of three types:
- In the connected component containing vertex $v_i$, find the vertex label that is the $k_i$-th smallest. If it does not exist, output $-1$. The connected component containing $v_i$ means the set of all vertices reachable from $v_i$ by edges.
- Add an edge connecting vertices $u_i$ and $v_i$ to the graph.
- Roll back to the state right after the $x_i$-th operation is executed.
Find the answers to all queries of the first type.
Input Format
The first line contains three integers $n$, $q$, $g$ ($1 \leq n, q \leq 5 \cdot 10^5$, $0 \leq g \leq 9$).
Each of the following lines describes one query:
- Type 1 query: $v_i$, $k_i$ ($1 \leq v_i, k_i \leq n$).
- Type 2 query: $v_i$, $u_i$ ($1 \leq v_i, u_i \leq n$).
- Type 3 query: $x_i$ ($0 \leq x_i < i$).
Output Format
For each type 1 query, output the answer to that query.
Explanation/Hint
### Scoring
- (6 points): $n, q \leq 100$; there are no type 2 or type 3 operations.
- (7 points): $n, q \leq 100$; there are no type 3 operations.
- (4 points): $n, q \leq 100$.
- (9 points): $n, q \leq 3 \cdot 10^5$; it is guaranteed that in type 2 operations $|v_i - u_i| = 1$; there are no type 3 queries.
- (8 points): $n, q \leq 3 \cdot 10^5$; there are no type 3 queries.
- (10 points): $n, q \leq 3 \cdot 10^5$; it is guaranteed that in type 2 operations $|v_i - u_i| = 1$.
- (19 points): $n, q \leq 10^5$.
- (17 points): $n, q \leq 3 \cdot 10^5$.
- (20 points): No additional constraints.
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