Dfs

Problem Given the root of a binary search tree and the lowest and highest boundaries as low and high, trim the tree so that all its elements lies in [low, high]. Trimming the tree should not change the relative structure of the elements that will remain in the tree (i.e., any node’s descendant should remain a descendant). It can be proven that there is a unique answer. Return the root of the trimmed binary search tree. Note that the root may change depending on the given bounds. ...

Problem There is a bi-directional graph with n vertices, where each vertex is labeled from 0 to n - 1 (inclusive). The edges in the graph are represented as a 2D integer array edges, where each edges[i] = [ui, vi] denotes a bi-directional edge between vertex ui and vertex vi. Every vertex pair is connected by at most one edge, and no vertex has an edge to itself. You want to determine if there is a valid path that exists from vertex source to vertex destination. ...

Problem There is a bi-directional graph with n vertices, where each vertex is labeled from 0 to n - 1 (inclusive). The edges in the graph are represented as a 2D integer array edges, where each edges[i] = [ui, vi] denotes a bi-directional edge between vertex ui and vertex vi. Every vertex pair is connected by at most one edge, and no vertex has an edge to itself. You want to determine if there is a valid path that exists from vertex source to vertex destination. ...

Problem Given a list of lists containing elements, write a function that prints out the permutations of of the elements such that, each of the permutation set contains only 1 element from each list and there are no duplicates in the list of permutation sets. Examples Example 1: Input: lists = [ [a1, b1, c1], [a2, b2] ] Output: [ [a1, a2], [a1, b2], [b1, a2], [b1, b2], [c1, a2], [c1, b2] ] Explanation: Note that [a1, a2] is same as [a2, a1] in terms of combination, though they are separate permutation. ...