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There is a stream of n (idKey, value) pairs arriving in an arbitrary order, where idKey is an integer between 1 and n and value is a string. No two pairs have the same id. Design a stream that returns the values in increasing order of their IDs by returning a chunk (list) of values…
You have a bomb to defuse, and your time is running out! Your informer will provide you with a circular array code of length of n and a key k. To decrypt the code, you must replace every number. All the numbers are replaced simultaneously. As code is circular, the next element of code[n-1] is…
A string is good if there are no repeated characters. Given a string s, return the number of good substrings of length three in s. Note that if there are multiple occurrences of the same substring, every occurrence should be counted. A substring is a contiguous sequence of characters in a string. Example 1: Input:…
The letter value of a letter is its position in the alphabet starting from 0 (i.e. ‘a’ -> 0, ‘b’ -> 1, ‘c’ -> 2, etc.). The numerical value of some string of lowercase English letters s is the concatenation of the letter values of each letter in s, which is then converted into an…
Given two n x n binary matrices mat and target, return true if it is possible to make mat equal to target by rotating mat in 90-degree increments, or false otherwise. Example 1: Input: mat = [[0,1],[1,0]], target = [[1,0],[0,1]]Output: trueExplanation: We can rotate mat 90 degrees clockwise to make mat equal target. Example 2:…
You are given an array of strings words (0-indexed). In one operation, pick two distinct indices i and j, where words[i] is a non-empty string, and move any character from words[i] to any position in words[j]. Return true if you can make every string in words equal using any number of operations, and false otherwise….
Given a 0-indexed integer array nums, return true if it can be made strictly increasing after removing exactly one element, or false otherwise. If the array is already strictly increasing, return true. The array nums is strictly increasing if nums[i – 1] < nums[i] for each index (1 <= i < nums.length). Example 1: Input:…
Given an integer array nums of length n, you want to create an array ans of length 2n where ans[i] == nums[i] and ans[i + n] == nums[i] for 0 <= i < n (0-indexed). Specifically, ans is the concatenation of two nums arrays. Return the array ans. Example 1: Input: nums = [1,2,1]Output: [1,2,1,1,2,1]Explanation:…
Given a string s, return the number of unique palindromes of length three that are a subsequence of s. Note that even if there are multiple ways to obtain the same subsequence, it is still only counted once. A palindrome is a string that reads the same forwards and backwards. A subsequence of a string…
Alice and Bob take turns playing a game, with Alice starting first. You are given a string num of even length consisting of digits and ‘?’ characters. On each turn, a player will do the following if there is still at least one ‘?’ in num: The game ends when there are no more ‘?’…