You are given the head of a singly linked list. For each node in the list, find the value of the next node that has a strictly larger value than the current node. If no such node exists, return 0 for that node. Return the result as an array where the value at index i represents the next greater node for the i-th node.
You are given a grid of size m x n where each cell is either land (1) or sea (0). Your task is to determine the number of land cells that are completely enclosed by sea cells. A land cell is considered enclosed if it cannot reach the boundary of the grid via other land cells.
You are given a list of query strings and a pattern. A query string matches the pattern if you can insert lowercase English letters into the pattern such that it becomes the query string. Each character from the pattern must be placed in order without changing its relative positions, and you may not add any characters that are not in the pattern.
You are given a set of video clips from a sporting event that lasts a specified duration in seconds. The clips may overlap and have varying lengths. The goal is to determine the minimum number of clips required to cover the entire event. If it’s impossible to cover the entire event, return -1.
You are given the root of a binary tree. Your task is to find the maximum absolute difference between the values of two nodes, where one node is an ancestor of the other. Specifically, you need to find the largest value of |a.val - b.val|, where node a is an ancestor of node b.
Given an array of integers, you need to return the length of the longest subsequence where the difference between consecutive elements is constant. A subsequence is derived by deleting some elements without changing the order of the remaining elements. A sequence is considered arithmetic if the difference between consecutive elements remains the same.