You are given a list of equations and their corresponding values, where each equation represents a division between two variables. Your task is to determine the result of several queries asking for the division result of two given variables.
You are given an m x n grid representing an island, where each cell contains an integer representing the height above sea level. The island borders both the Pacific and Atlantic Oceans. The Pacific Ocean touches the left and top edges of the grid, and the Atlantic Ocean touches the right and bottom edges. Water can flow from one cell to an adjacent cell if the adjacent cell’s height is less than or equal to the current cell’s height. The task is to find all the cells where water can flow to both oceans.
You are given an n-ary tree where each node contains a value and a list of its children. Your task is to return the level order traversal of the tree’s nodes. Nodes are grouped by their level, with the root node at level 0. Each node’s children are separated by a null value in the level order serialization.
You are given two gene strings, startGene and endGene, both consisting of 8 characters. You also have a gene bank of valid gene strings that can be mutated into one another. A mutation is defined as changing one character at a time, and the mutated gene string must exist in the gene bank. Your task is to determine the minimum number of mutations needed to transform startGene into endGene. If transformation is impossible, return -1.
Design an algorithm to serialize and deserialize a binary search tree (BST). Serialization is converting the tree to a string format, while deserialization reconstructs the tree from this string. The goal is to ensure that the BST can be serialized to a compact string and can be accurately deserialized back into the original tree structure.
