Find Unique Binary String Given an array of strings nums containing n unique binary strings each of length n, return a binary string of length *n that does not appear in nums. If there are multip...

The k-th Lexicographical String of All Happy Strings of Length n A happy string is a string that: consists only of letters of the set ['a', 'b', 'c']. s[i] != s[i + 1] for all values of i from 1...

Construct Smallest Number From DI String You are given a 0-indexed string pattern of length n consisting of the characters ‘I’ meaning increasing and ‘D’ meaning decreasing. A 0-indexed string n...

Letter Tile Possibilities You have n  tiles, where each tile has one letter tiles[i] printed on it. Return the number of possible non-empty sequences of letters you can make using the letters pr...

Construct the Lexicographically Largest Valid Sequence Given an integer n, find a sequence that satisfies all of the following: The integer 1 occurs once in the sequence. Each integer between 2 ...

Find the Punishment Number of an Integer Given a positive integer n, return the punishment number of n. The punishment number of n is defined as the sum of the squares of all integers i such tha...

Product of the Last K Numbers Design an algorithm that accepts a stream of integers and retrieves the product of the last k integers of the stream. Implement the ProductOfNumbers class: Product...

Minimum Operations to Exceed Threshold Value II You are given a 0-indexed integer array nums, and an integer k. In one operation, you will: Take the two smallest integers x and y in nums. Remov...

Max Sum of a Pair With Equal Sum of Digits You are given a 0-indexed array nums consisting of positive integers. You can choose two indices i and j, such that i != j, and the sum of digits of the...

Remove All Occurrences of a Substring Given two strings s and part, perform the following operation on s until all occurrences of the substring part are removed: Find the **leftmost** occurrence...