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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….
A square triple (a,b,c) is a triple where a, b, and c are integers and a2 + b2 = c2. Given an integer n, return the number of square triples such that 1 <= a, b, c <= n. Example 1: Input: n = 5Output: 2Explanation: The square triples are (3,4,5) and (4,3,5). Example 2:…
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…
There are several cards arranged in a row, and each card has an associated number of points. The points are given in the integer array cardPoints. In one step, you can take one card from the beginning or from the end of the row. You have to take exactly k cards. Your score is the…