RP-3

var StreamChecker = function(words) {    
    this.tree = PrefixTree();
    this.maxWordLength = 0;
    words.forEach((word) => {
        this.tree.add(word.split('').reverse().join(''));
        this.maxWordLength = Math.max(this.maxWordLength, word.length);
    });
    this.storage = []; // should be a queue! This is O(n) time as opposed to a queues O(1)
};

RP-3

/**
 * Initialize your data structure here.
 */
var AllOne = function() {
    this.counter = new Map(); // [key: int]
    this.index = new Map(); // [int: ListNode]
    this.head = new ListNode(); // prev, next, set<key>
    this.tail = new ListNode();
    this.head.prev = this.tail;
    this.tail.next = this.head;

RP-3

/**
 * @param {number} capacity
 */
var LRUCache = function(capacity) {
    this.size = 0;
    this.capacity = capacity;
    this.index = new Map(); // <key: ListNode>

    this.head = new ListNode(null, null);
    this.tail = new ListNode(null, null);

RP-3

/**
 * @param {number[][]} obstacleGrid
 * @return {number}
 */
var uniquePathsWithObstacles = function(obstacleGrid) {
    
    const memo = new Array(obstacleGrid.length)
        .fill(0)
        .map(() => new Array(obstacleGrid[0].length).fill(null));
    

RP-3

/**
 * @param {number[][]} grid
 * @return {number}
 */
var uniquePathsIII = function(grid) {
    
    const visited = new Array(grid.length).fill(0).map(() => new Array(grid[0].length).fill(0));
    let visitedCount = 0;
    const squaresToVisit = countNonObstacleSquares(grid);
    

RP-3

/**
 * @param {number[]} nums
 * @return {string}
 */
var largestNumber = function(nums) {
    
    const result = nums
    .map((num) => num.toString())
    .sort((a, b) => {
        const aBeforeB = parseInt(`${a}${b}`, 10);

RP-3

const Queue = function(){
    this.storage = new Array(10);
    this.start = -1; // index of first element in array
    this.end = -1; // index of last element in array
};

Queue.prototype.size = function(){
    if(this.start === -1) return 0;
    if(this.start < this.end) return this.end - this.start + 1;
    if(this.start === this.end) return 1;

RP-3

/**
 * @param {number[]} nums
 * @param {number} k
 * @return {number[]}
 */
var maxSlidingWindow = function(nums, k) {
    
    if(!nums.length || !k) return []; // because leetcode
    
    const result = [];

RP-3

var isOneEditDistance = function(s, t) {
    if(Math.abs(s.length - t.length) > 1) return false;
    if(s === t) return false;
    
    let longer; let shorter;
    if(s.length > t.length){
        [longer, shorter] = [s, t];
    }else{
        [longer, shorter] = [t, s];
    }

RP-3

// recursive
var calculateMinimumHP = function(dungeon) {
    
    const [m, n] = [dungeon.length, dungeon[0].length];
    const dp = new Array(m).fill(0).map(() => new Array(n).fill(null));
    
    const traverse = (i, j) => {
        
        if(i === m) return Infinity;
        if(j === n) return Infinity;