287. Find the Duplicate Number
Given an array nums containing n + 1 integers where each integer is between 1 and n (inclusive), pro…
142. Linked List Cycle II
Given a linked list, return the node where the cycle begins. If there is no cycle, return null. Note…
49. Group Anagrams
Given an array of strings, group anagrams together. For example, given: [“eat”, “tea”, “tan”, “ate”,…
346. Moving Average from Data Stream
Given a stream of integers and a window size, calculate the moving average of all integers in the sl…
155. Min Stack
Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. pu…
225. Implement Stack using Queues
Implement the following operations of a stack using queues. push(x) — Push element x onto stac…
232. Implement Queue using Stacks
Implement the following operations of a queue using stacks. push(x) — Push element x to the ba…
LeetCode – 141. Linked List Cycle
Given a linked list, determine if it has a cycle in it. Follow up: Can you solve it without using ex…
LeetCode – 160. Intersection of Two Linked Lists
Write a program to find the node at which the intersection of two singly linked lists begins. …
LeetCode – 234. Palindrome Linked List
Given a singly linked list, determine if it is a palindrome. Follow up: Could you do it in O(n) time…