📄️ 217. Contains Duplicates
Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct.
📄️ 242. Valid Anagram
Given two strings s and t, return true if t is an anagram of s, and false otherwise.
📄️ 1. Two Sum
Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.
📄️ 49. Group Anagrams
Given an array of strings strs, group the anagrams together. You can return the answer in any order.
📄️ 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.
📄️ 238. Product of Array Except Self
Given an integer array nums, return an array answer such that answer[i] is equal to the product of all the elements of nums except nums[i].
📄️ 36. Valid Sudoku
Determine if a 9 x 9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules:
📄️ 271. Encode and Decode Strings
Design an algorithm to encode a list of strings to a string. The encoded string is then sent over the network and is decoded back to the original list of strings.
📄️ 128. Longest Consecutive Sequence
Given an unsorted array of integers nums, return the length of the longest consecutive elements sequence.