1519. Number of Nodes in the Sub-Tree With the Same Label

Medium

2.1K

777

You are given a tree (i.e. a connected, undirected graph that has no cycles) consisting of `n`

nodes numbered from `0`

to `n - 1`

and exactly `n - 1`

`edges`

. The **root** of the tree is the node `0`

, and each node of the tree has **a label** which is a lower-case character given in the string `labels`

(i.e. The node with the number `i`

has the label `labels[i]`

).

The `edges`

array is given on the form `edges[i] = [a`

, which means there is an edge between nodes _{i}, b_{i}]`a`

and _{i}`b`

in the tree._{i}

Return *an array of size n* where

`ans[i]`

is the number of nodes in the subtree of the `i`^{th}

node which have the same label as node `i`

.A subtree of a tree `T`

is the tree consisting of a node in `T`

and all of its descendant nodes.

**Example 1:**

Input:n = 7, edges = [[0,1],[0,2],[1,4],[1,5],[2,3],[2,6]], labels = "abaedcd"Output:[2,1,1,1,1,1,1]Explanation:Node 0 has label 'a' and its sub-tree has node 2 with label 'a' as well, thus the answer is 2. Notice that any node is part of its sub-tree. Node 1 has a label 'b'. The sub-tree of node 1 contains nodes 1,4 and 5, as nodes 4 and 5 have different labels than node 1, the answer is just 1 (the node itself).

**Example 2:**

Input:n = 4, edges = [[0,1],[1,2],[0,3]], labels = "bbbb"Output:[4,2,1,1]Explanation:The sub-tree of node 2 contains only node 2, so the answer is 1. The sub-tree of node 3 contains only node 3, so the answer is 1. The sub-tree of node 1 contains nodes 1 and 2, both have label 'b', thus the answer is 2. The sub-tree of node 0 contains nodes 0, 1, 2 and 3, all with label 'b', thus the answer is 4.

**Example 3:**

Input:n = 5, edges = [[0,1],[0,2],[1,3],[0,4]], labels = "aabab"Output:[3,2,1,1,1]

**Constraints:**

`1 <= n <= 10`

^{5}`edges.length == n - 1`

`edges[i].length == 2`

`0 <= a`

_{i}, b_{i}< n`a`

_{i}!= b_{i}`labels.length == n`

`labels`

is consisting of only of lowercase English letters.

Accepted

78.1K

Submissions

141.2K

Acceptance Rate

55.3%

Seen this question in a real interview before?

1/4

Yes

No

Discussion (0)

Related Topics

Copyright ©️ 2023 LeetCode All rights reserved