Count Unreachable Pairs of Nodes in an Undirected Graph
You are given an integer n. There is an undirected graph with n nodes, numbered from 0 to n - 1. You are given a 2D integer array edges where edges[i] = [ai, bi] denotes that there exists an undirected edge connecting nodes ai and bi.
Return the number of pairs of different nodes that are unreachable from each other.
Example 1
Input
n = 3, edges = [[0,1],[0,2],[1,2]]Output
0There are no pairs of nodes that are unreachable from each other, so the answer is 0.
Example 2
Input
n = 7, edges = [[0,2],[0,5],[2,4],[1,6],[5,4]]Output
14There are 14 pairs of nodes that are unreachable from each other.
Constraints
- 1 <= n <= 10^5
- 0 <= edges.length <= 2 * 10^5
- edges[i].length == 2
- 0 <= ai, bi < n
- ai != bi
- There are no repeated edges.