In a binary tree, the root node is at depth 0, and children of each depth k node are at depth k+1.
Two nodes of a binary tree are cousins if they have the same depth, but have different parents.
We are given the root of a binary tree with unique values, and the values x and y of two different nodes in the tree.
Return true if and only if the nodes corresponding to the values x and y are cousins.
Example 1:
Input: root = [1,2,3,4], x = 4, y = 3 Output: false Example 2:
Input: root = [1,2,3,null,4,null,5], x = 5, y = 4 Output: true Example 3:
Input: root = [1,2,3,null,4], x = 2, y = 3 Output: false Note:
The number of nodes in the tree will be between 2 and 100. Each node has a unique integer value from 1 to 100.
In a given grid, each cell can have one of three values:
the value 0 representing an empty cell; the value 1 representing a fresh orange; the value 2 representing a rotten orange. Every minute, any fresh orange that is adjacent (4-directionally) to a rotten orange becomes rotten.
Return the minimum number of minutes that must elapse until no cell has a fresh orange. If this is impossible, return -1 instead.
Example 1:
Input: [[2,1,1],[1,1,0],[0,1,1]] Output: 4 Example 2:
Input: [[2,1,1],[0,1,1],[1,0,1]] Output: -1 Explanation: The orange in the bottom left corner (row 2, column 0) is never rotten, because rotting only happens 4-directionally. Example 3:
Input: [[0,2]] Output: 0 Explanation: Since there are already no fresh oranges at minute 0, the answer is just 0. Note:
1 <= grid.length <= 10 1 <= grid[0].length <= 10 grid[i][j] is only 0, 1, or 2.
Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then right to left for the next level and alternate between).
For example: Given binary tree [3,9,20,null,null,15,7],
3
/ \
9 20
/ \
15 7 return its zigzag level order traversal as:
[
[3],
[20,9],
[15,7]
]