mediumBreadth First SearchDepth First SearchGraphUnion Find 0 views

Count Unreachable Pairs of Nodes in an Undirected Graph

You are given an integer n.

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.

Count Unreachable Pairs of Nodes in an Undirected Graph diagram

Example 1

Input: n = 3, edges = [[0,1],[0,2],[1,2]]

Output: 0

Explanation: There are no pairs of nodes that are unreachable from each other. Therefore, we return 0.

Example 2

Input: n = 7, edges = [[0,2],[0,5],[2,4],[1,6],[5,4]]

Output: 14

Explanation: There are 14 pairs of nodes that are unreachable from each other: [[0,1],[0,3],[0,6],[1,2],[1,3],[1,4],[1,5],[2,3],[2,6],[3,4],[3,5],[3,6],[4,6],[5,6]]. Therefore, we return 14.

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.

Hints

Companies

No companies reported yet.

Discussion

Sign in to join the discussion.

Loading discussion...

Test results

No test cases yet.