Maximum Depth of Binary Tree Problem Given a binary tree, find its maximum depth. Definition A binary tree’s maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node. The number of nodes along the longest path from the root node down to the farthest leaf node. Depth of root node is 0. Example Example 1 ...
Problem Given a string s, partition s such that every substring of the partition is a palindrome. Return all possible palindrome partitioning of s. Definition Palindrome Definition Examples Example 1: Input: s = "aab" Output: [ ["a","a","b"],["aa","b"] ] Example 2: Input: s = "a" Output: [ ["a"] ] ...
Problem An image is represented by an m x n integer grid image where image[i][j] represents the pixel value of the image. You are also given three integers sr, sc, and color. You should perform a flood fill on the image starting from the pixel image[sr][sc]. To perform a flood fill, consider the starting pixel, plus any pixels connected 4-directionally to the starting pixel of the same color as the starting pixel, plus any pixels connected 4-directionally to those pixels (also with the same color), and so on. Replace the color of all of the aforementioned pixels with color. ...
Problem Given an m x n 2D binary grid grid which represents a map of '1's (land) and '0's (water), return the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by water. Examples Example 1: Input: grid = [ ["1","1","1","1","0"], ["1","1","0","1","0"], ["1","1","0","0","0"], ["0","0","0","0","0"] ] Output: 1 ...
Problem Given a string s and a dictionary of words dict, determine if s can be segmented into a space-separated sequence of one or more dictionary words. Examples Example 1: Input: s = "leetcode", wordDict = ["leet","code"] Output: true Explanation: Return true because "leetcode" can be segmented as "leet code". Example 2: ...
Problem Given a binary tree and a sum, find all root-to-leaf paths where each path’s sum equals the given sum. Examples Example 1: graph TD; A[5] --> B[4] & C[8] B --> D[11] & E[null] C --> F[13] & G[4] D --> H[7] & I[2] G --> L[5] & M[1] style A fill:#f9f style B fill:#f9f style C fill:#f9f style D fill:#f9f style I fill:#f9f style G fill:#f9f style L fill:#f9f ...
Problem You are given two m x n binary matrices grid1 and grid2 containing only 0’s (representing water) and 1’s (representing land). An island is a group of 1’s connected 4-directionally (horizontal or vertical). Any cells outside of the grid are considered water cells. An island in grid2 is considered a sub-island if there is an island in grid1 that contains all the cells that make up this island in grid2. ...
Problem You are given an m x n binary grid grid where 1 represents land and 0 represents water. An island is a maximal 4-directionally (horizontal or vertical) connected group of 1’s. The grid is said to be connected if we have exactly one island, otherwise is said disconnected. In one day, we are allowed to change any single land cell (1) into a water cell (0). ...
Problem In this problem, a tree is an undirected graph that is connected and has no cycles. You are given a graph that started as a tree with n nodes labeled from 1 to n, with one additional edge added. The added edge has two different vertices chosen from 1 to n, and was not an edge that already existed. The graph is represented as an array edges of length n where edges[i] = [ai, bi] indicates that there is an edge between nodes ai and bi in the graph. ...
Binary Tree Cameras Problem Problem You are given the root of a binary tree. We install cameras on the tree nodes where each camera at a node can monitor its parent, itself, and its immediate children. Return the minimum number of cameras needed to monitor all nodes of the tree. Examples Example 1: ...