In a city grid, buildings are represented by an n x n matrix where each element corresponds to the height of a building at a specific location. You can increase the height of any building in the city grid, but the increased height should not alter the skyline of the city when viewed from any of the four cardinal directions (north, south, east, and west). Your task is to calculate the maximum sum of the heights that can be added to the buildings without changing the skyline.
You have two types of soup: A and B, with an initial volume of n ml of each. You can serve soup using four possible operations, each with a 25% chance of being chosen randomly. When serving, the amounts of soups A and B used are specified by each operation. If there is insufficient soup for a full operation, serve as much as possible. The process stops when one of the soups runs out. Return the probability that soup A will be exhausted first, plus half the probability that both soups will be exhausted at the same time.
You are given a string s and a list of query words. Each word in the query list is said to be ‘stretchy’ if it can be transformed into string s by extending groups of adjacent letters. You can extend a group of letters (e.g., ‘a’, ‘bb’, ‘ccc’) as long as its length is at least 3. For example, if s = ‘heeellooo’, you could extend ’e’ and ‘o’ to make ‘hello’ stretchy. Return the number of query strings that can be stretched to become s.
You are given a list of count-paired domains, where each entry consists of a number followed by a domain name. The number represents the number of visits to that domain. A domain may also have subdomains, and visiting a subdomain also counts as visiting its parent domains. Your task is to return the count of visits for each domain and its subdomains.
You are given an integer array ’nums’ and an integer ‘k’. You can partition the array into at most ‘k’ non-empty adjacent subarrays. The score of a partition is defined as the sum of the averages of each subarray. Your goal is to return the maximum score that can be achieved by partitioning the array in any possible way, with each partition’s score calculated as the sum of averages of its subarrays.
You are given the root of a binary tree. Your task is to remove all subtrees in the tree that do not contain at least one node with the value 1. A subtree is defined as the node and all its descendants. Return the modified tree.
