https://leetcode.com/problems/spiral-matrix/ Let inputMatrix be a matrix of numRows rows and numColscolumns. Look carefully at the image above. Instead of following numerical order, we’ll copy the outer edges of the array, in order. Then we’ll move on to the inner edges. These edges create the spiral. …

Corporate Flight Bookings Corporate Flight Bookings - LeetCode Can you solve this real interview question? Corporate Flight Bookings - There are n flights that are labeled from 1 to…leetcode.com So the idea is that every booking will be update to a range, and for range update, we have a special data structure Difference Array which could handle it in O(1) time. In a nutshell, a difference array is an seperated array that stores the difference of adjacent elements of…

Given a string s='abcde' and a dictionary of valid words valid_words=['a', 'ab', 'cd', 'cde', 'e'], return all possible ways to break down the string into only valid words (e.g. ['ab cd e', 'ab cde']). Leetcode Link We can decompose this problem by first identifying which valid words are also prefixes…

The car manufacturer Honda holds their distribution system in the form of a tree (not necessarily binary). The root is the company itself, and every node in the tree represents a car distributor that receives cars from the parent node and ships them to its children nodes. The leaf nodes…

Given a dictionary dict, write a function flattenDictionary that returns a flattened version of it. Assume that values are either an integer, a string, or another dictionary. If a certain key is empty, it should be excluded from the output (see e in the example below). input: dict =…

Algorithm: Find the Strings from root to start and root to dest. And then remove the common prefix of both the strings. Replace each character of start string with ‘U’ . And concatinate the start string with the reversed dest string. /** * Definition for a binary tree node. *…

class LRUCache { private Map<Integer, Node> map; final Node head = new Node(); final Node tail = new Node(); private int capacity; public LRUCache(int capacity) { this.map = new HashMap<>(capacity); this.capacity = capacity…

to implement following functions in HashMap: put(), get(), remove(), size(),keySet(),containsKey() We will be using Arrays of LinkedList . Each linked List will represent a bucket. After hashing of keys, the key will be added to its corresponding bucket. Our Node will look like this . private class HMNode{…

class Trie { class TrieNode{ Map<Character,TrieNode> children = new HashMap<>(); boolean isLeaf; } private TrieNode root; /** Initialize your data structure here. */ public Trie() { root= new TrieNode(); } /** Inserts a word into the trie. */ public void insert(String word) { TrieNode node = root; for(char c : word.toCharArray()){ if(!node.children.containsKey(c)){ node.children.put(c,new TrieNode()); } node = node.children.get(c); } node.isLeaf= true; } /** Returns if the word is in the trie. */ public boolean search(String word) { TrieNode p = root; for(char c : word.toCharArray()) { if(!p.children.containsKey(c)) { return false; } p = p.children.get(c); } return p.isLeaf; } /** Returns if there is any word in the trie that starts with the given prefix. */ public boolean startsWith(String prefix) { TrieNode p = root; for(char c : prefix.toCharArray()) { if(!p.children.containsKey(c)) { return false; } p = p.children.get(c); } return true; } }