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Redundant Connection
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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 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.

Return an edge that can be removed so that the resulting graph is a tree. If there are multiple answers, return the edge that occurs last in the input.

Example 1:

Input:
3
1 2
1 3
2 3
Output: 2 3

Example 2:

Input:
4
1 2
2 3
3 4
1 4
2 4
Output: 2 4

Input format: First line: n. Next n lines: edges.

Output format: The redundant edge.

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