题目描述
A direced graph is strongly connected if every two nodes are reachable from each other. In a strongly connected component of a directed graph, every two nodes of the component are mutually reachable.
Constraints
- 1 ≤ |V| ≤ 10,000
- 0 ≤ |E| ≤ 30,000
- 1 ≤ Q ≤ 100,000
Input
A directed graph G(V, E) and a sequence of queries where each query contains a pair of nodes u and v.
|V| |E|
s0 t0
s1 t1
:
s|E|-1 t|E|-1
Q
u0 v0
u1 v1
:
uQ-1 vQ-1
|V| is the number of nodes and |E| is the number of edges in the graph. The graph nodes are named with the numbers 0, 1,..., |V|-1 respectively.
si and ti represent source and target nodes of i-th edge (directed).
ui and vi represent a pair of nodes given as the i-th query.
Output
For each query, pinrt "1" if the given nodes belong to the same strongly connected component, "0" otherwise.
Example
Input
5 6
0 1
1 0
1 2
2 4
4 3
3 2
4
0 1
0 3
2 3
3 4
Output
1
0
1
1
输入格式
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输出格式
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