Practice Redundant Connection

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Medium#684

LeetCode Problem

Redundant Connection

Depth-First Search Breadth-First Search Union Find Graph

Problem Statement

In this problem, a tree is an undirected graph that is connected and has no cycles. You are given a graph that started as a tree with n nodes labeled from 1 to n, with one additional edge added. The added edge has two different vertices chosen from 1 to n, and was not an edge that already existed. The graph is represented as an array edges of length n where edges[i] = [ai, bi] indicates that there is an edge between nodes ai and bi in the graph. Return an edge that can be removed so that the resulting graph is a tree of n nodes. If there are multiple answers, return the answer that occurs last in the input.

Source: Redundant Connection on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input

edges = [[1,2],[1,3],[2,3]]

Output

[2,3]

# Example 2

Input

edges = [[1,2],[2,3],[3,4],[1,4],[1,5]]

Output

[1,4]

Constraints

n == edges.length

3 <= n <= 1000

edges[i].length == 2

1 <= ai < bi <= edges.length

ai != bi

There are no repeated edges.

The given graph is connected.

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