Class Solution
- java.lang.Object
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- g0301_0400.s0310_minimum_height_trees.Solution
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public class Solution extends Object
310 - Minimum Height Trees.Medium
A tree is an undirected graph in which any two vertices are connected by exactly one path. In other words, any connected graph without simple cycles is a tree.
Given a tree of
n
nodes labelled from0
ton - 1
, and an array ofn - 1
edges
whereedges[i] = [ai, bi]
indicates that there is an undirected edge between the two nodesai
andbi
in the tree, you can choose any node of the tree as the root. When you select a nodex
as the root, the result tree has heighth
. Among all possible rooted trees, those with minimum height (i.e.min(h)
) are called minimum height trees (MHTs).Return a list of all MHTs’ root labels. You can return the answer in any order.
The height of a rooted tree is the number of edges on the longest downward path between the root and a leaf.
Example 1:
Input: n = 4, edges = [[1,0],[1,2],[1,3]]
Output: [1]
Explanation: As shown, the height of the tree is 1 when the root is the node with label 1 which is the only MHT.
Example 2:
Input: n = 6, edges = [[3,0],[3,1],[3,2],[3,4],[5,4]]
Output: [3,4]
Constraints:
1 <= n <= 2 * 104
edges.length == n - 1
0 <= ai, bi < n
ai != bi
- All the pairs
(ai, bi)
are distinct. - The given input is guaranteed to be a tree and there will be no repeated edges.
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Constructor Summary
Constructors Constructor Description Solution()
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