You are given two integer arrays, source and target, both of length n, and an array allowedSwaps containing pairs of indices where swapping is allowed. You can perform multiple swaps between the specified pairs to minimize the Hamming distance between source and target. The Hamming distance is the number of indices where the elements of source and target differ.
You are given two m x n binary matrices, grid1 and grid2, where each cell can either be 0 (representing water) or 1 (representing land). An island is a group of connected 1’s, connected either horizontally or vertically. An island in grid2 is considered a sub-island if there is a corresponding island in grid1 that contains all the cells of the island in grid2. Your task is to determine the number of sub-islands in grid2.
You are given a graph with n vertices labeled from 0 to n-1 (inclusive) and edges connecting pairs of vertices. Your task is to determine if there exists a valid path from a given source vertex to a destination vertex. The graph is undirected, and each pair of vertices is connected by at most one edge. The vertices are connected by edges as given in the input.
You are given an undirected graph with n nodes and a list of edges connecting the nodes. The goal is to find the number of pairs of distinct nodes that are unreachable from each other.
You are given a tree with n nodes and n - 1 edges, where nodes are labeled from 0 to n - 1. Additionally, a list of restricted nodes is provided. Your goal is to determine the maximum number of nodes that can be visited starting from node 0, without passing through any restricted node. Node 0 itself is not restricted.
You are given a stream of n distinct videos, each represented by a unique number from 1 to n. You need to design a data structure that tracks the longest prefix of uploaded videos at any point in time. A prefix is considered uploaded if all videos from 1 to i (inclusive) have been uploaded to the server.