You are given a reference to a node in a connected, undirected graph. Each node in the graph contains a value (integer) and a list of its neighbors. Your task is to return a deep copy of the entire graph starting from the given node.
You are given a set of courses and a list of prerequisites. Each prerequisite is a pair of courses where the second course must be taken before the first one. Determine if it is possible to complete all courses based on these prerequisites. If there are cycles in the dependencies, it would be impossible to finish all courses.
You are given a tree with ’n’ nodes labeled from 0 to n-1, represented by ’n-1’ edges. Your task is to find all roots that minimize the height of the tree. The height of a tree is defined as the number of edges in the longest downward path from the root to any leaf.
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 a matrix where each element indicates if two cities are directly connected. Your task is to determine the number of provinces formed by the cities. A province is a group of directly or indirectly connected cities.
