java.lang.Object
g0801_0900.s0834_sum_of_distances_in_tree.Solution

public class Solution extends Object
834 - Sum of Distances in Tree.<p>Hard</p> <p>There is an undirected connected tree with <code>n</code> nodes labeled from <code>0</code> to <code>n - 1</code> and <code>n - 1</code> edges.</p> <p>You are given the integer <code>n</code> and the array <code>edges</code> where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>]</code> indicates that there is an edge between nodes <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> in the tree.</p> <p>Return an array <code>answer</code> of length <code>n</code> where <code>answer[i]</code> is the sum of the distances between the <code>i<sup>th</sup></code> node in the tree and all other nodes.</p> <p><strong>Example 1:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2021/07/23/lc-sumdist1.jpg" alt="" /></p> <p><strong>Input:</strong> n = 6, edges = [[0,1],[0,2],[2,3],[2,4],[2,5]]</p> <p><strong>Output:</strong> [8,12,6,10,10,10]</p> <p><strong>Explanation:</strong> The tree is shown above.</p> <p>We can see that dist(0,1) + dist(0,2) + dist(0,3) + dist(0,4) + dist(0,5) equals 1 + 1 + 2 + 2 + 2 = 8.</p> <p>Hence, answer[0] = 8, and so on.</p> <p><strong>Example 2:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2021/07/23/lc-sumdist2.jpg" alt="" /></p> <p><strong>Input:</strong> n = 1, edges = []</p> <p><strong>Output:</strong> [0]</p> <p><strong>Example 3:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2021/07/23/lc-sumdist3.jpg" alt="" /></p> <p><strong>Input:</strong> n = 2, edges = [[1,0]]</p> <p><strong>Output:</strong> [1,1]</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= n <= 3 * 10<sup>4</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 <= a<sub>i</sub>, b<sub>i</sub> < n</code></li> <li><code>a<sub>i</sub> != b<sub>i</sub></code></li> <li>The given input represents a valid tree.</li> </ul>
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • sumOfDistancesInTree

      public int[] sumOfDistancesInTree(int n, int[][] edges)