Jackson.tmm

LeetCode 289 - Game of Life

According to Wikipedia’s article: “The Game of Life, also known simply as Life, is a cellular automaton devised by the British mathematician John Horton Conway in 1970.”

The board is made up of an m x n grid of cells, where each cell has an initial state: live (represented by a 1) or dead (represented by a 0). Each cell interacts with its eight neighbors (horizontal, vertical, diagonal) using the following four rules (taken from the above Wikipedia article):

LeetCode 682 - Baseball Game

You are keeping score for a baseball game with strange rules. The game consists of several rounds, where the scores of past rounds may affect future rounds’ scores.

At the beginning of the game, you start with an empty record. You are given a list of strings ops, where ops[i] is the ith operation you must apply to the record and is one of the following:

LeetCode 347 - Top K Frequent Elements

Given an integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order.

example

Input: nums = [1,1,1,2,2,3], k = 2
Output: [1,2]

Input: nums = [1], k = 1
Output: [1]

How can we solve this problem?

這一題需要我們返回K個數量最多的element。所以，我們可以使用map記錄我們array中element的個數，然後在把他們以<frequency,element>存到priority queue/max queue，最後只要返回priority queue中的k個element即可。

LeetCode 703 - Kth Largest Element in a Stream

Design a class to find the kth largest element in a stream. Note that it is the kth largest element in the sorted order, not the kth distinct element.

Implement KthLargest class:

• KthLargest(int k, int[] nums) Initializes the object with the integer k and the stream of integers nums.
• int add(int val) Appends the integer val to the stream and returns the element representing the kth largest element in the stream.

example: