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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 a 2D integer array ranges and two integers left and right. Each ranges[i] = [starti, endi] represents an inclusive interval between starti and endi. Return true if each integer in the inclusive range [left, right] is covered by at least one interval in ranges. Return false otherwise. An integer x is covered…
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….
are given a string num, representing a large integer. Return the largest-valued odd integer (as a string) that is a non-empty substring of num, or an empty string “” if no odd integer exists. A substring is a contiguous sequence of characters within a string. Example 1: Input: num = “52”Output: “5”Explanation: The only non-empty…
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:…
The product difference between two pairs (a, b) and (c, d) is defined as (a * b) – (c * d). Given an integer array nums, choose four distinct indices w, x, y, and z such that the product difference between pairs (nums[w], nums[x]) and (nums[y], nums[z]) is maximized. Return the maximum such product difference….