Leetcode

ProblemThere are n teams numbered from 0 to n - 1 in a tournament. Given a 0-indexed 2D boolean matrix grid of size n * n. For all i, j that 0 <= i, j <= n - 1 and i != j team i is stronger than team j if grid[i][j] == 1, otherwise, team j is stronger than team i. Team a will be the champion of the tournament if there is no team b that is stronger than team a. Return the team that will be the champion of the tournament. Example 1: 12345Input: grid = [[0,1],[0,0]]Output: 0Explanation: There ...

ProblemThere are n teams numbered from 0 to n - 1 in a tournament; each team is also a node in a DAG. You are given the integer n and a 0-indexed 2D integer array edges of length m representing the DAG, where edges[i] = [ui, vi] indicates that there is a directed edge from team ui to team vi in the graph. A directed edge from a to b in the graph means that team a is stronger than team b and team b is weaker than team a. Team a will be the champion of the tournament if there is no team b that is  ...

ProblemThere is an exam room with n seats in a single row labeled from 0 to n - 1. When a student enters the room, they must sit in the seat that maximizes the distance to the closest person. If there are multiple such seats, they sit in the seat with the lowest number. If no one is in the room, then the student sits at seat number 0. Design a class that simulates the mentioned exam room. Implement the ExamRoom class: ExamRoom(int n) Initializes the object of the exam room with the number of th ...

ProblemGiven an integer array nums and an integer k, return the length of the shortest non-empty subarray of nums with a sum of at least k. If there is no such subarray, return -1. A subarray is a contiguous part of an array. Example 1: 123Input: nums = [1], k = 1Output: 1 Example 2: 123Input: nums = [1,2], k = 4Output: -1 Example 3: 123Input: nums = [2,-1,2], k = 3Output: 3 Constraints: 1 <= nums.length <= 10^5 10^5 <= nums[i] <= 10^5 1 <= k <= 10^9 Solve想破頭 簡單說就是 找到第一組解後 ...

ProblemYou have a RecentCounter class which counts the number of recent requests within a certain time frame. Implement the RecentCounter class: RecentCounter() Initializes the counter with zero recent requests. int ping(int t) Adds a new request at time t, where t represents some time in milliseconds, and returns the number of requests that has happened in the past 3000 milliseconds (including the new request). Specifically, return the number of requests that have happened in the inclusive ran ...

ProblemYou are given an integer array deck. There is a deck of cards where every card has a unique integer. The integer on the ith card is deck[i]. You can order the deck in any order you want. Initially, all the cards start face down (unrevealed) in one deck. You will do the following steps repeatedly until all cards are revealed: Take the top card of the deck, reveal it, and take it out of the deck. If there are still cards in the deck then put the next top card of the deck at the bottom of t ...

ProblemYou are given an n x n integer matrix board where the cells are labeled from 1 to n^2 in a Boustrophedon style starting from the bottom left of the board (i.e. board[n - 1][0]) and alternating direction each row. You start on square 1 of the board. In each move, starting from square curr, do the following: Choose a destination square next with a label in the range [curr + 1, min(curr + 6, n^2)]. This choice simulates the result of a standard 6-sided die roll: i.e., there are always at mo ...

個人刷 leetcode 地方，不一定每題都為最佳最速解 多為 'Top Interview 150' & 'blink 75' 的選題，其中同一題目會出現在不同類型，所以會重複 多為 'Top Interview **150'** & 'blink 75' ****的選題，其中同一題目會出現在不同類型，所以會重複 下方勾勾完全沒作用，單純複習時方便，但重新整理或離開就刷新 演算法Binary Search入門 Leetcode-34-Find-First-and-Last-Position-of-Element-in-Sorted-Array Leetcode-35-Search-Insert-Position Leetcode-74-Search-a-2D-Matrix 進階 Depth-First Search Breadth-First Search入門 Leetcode-100-Same-Tree Leetcode-101-Symmetric-Tree Leetcode-22 ...

ProblemGiven two strings s and t of lengths m and n respectively, return the minimum window substring of 1s such that every character in 1t (including duplicates) is included in the window . If there is no such substring, return the empty string 1"" . The testcases will be generated such that the answer is unique. Example 1: 1234Input: s = "ADOBECODEBANC", t = "ABC"Output: "BANC"Explanation: The minimum window substring "BANC" includes 'A ...

ProblemGiven an integer array nums sorted in non-decreasing order, remove the duplicates in-place such that each unique element appears only once. The relative order of the elements should be kept the same. Then return the number of unique elements in nums. Consider the number of unique elements of nums to be k, to get accepted, you need to do the following things: Change the array nums such that the first k elements of nums contain the unique elements in the order they were present in nums ini ...