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Leetcode 2381: Shifting Letters II

You are given a string s consisting of lowercase English letters and a 2D array shifts. Each entry in the array represents a shift operation, where a segment of the string from starti to endi (inclusive) is shifted forward if directioni is 1, or backward if directioni is 0. A forward shift means replacing a character with the next letter in the alphabet (wrapping around from ‘z’ to ‘a’), and a backward shift means replacing a character with the previous letter (wrapping around from ‘a’ to ‘z’). You need to return the final string after all shifts are applied.

Leetcode 2389: Longest Subsequence With Limited Sum

You are given an integer array nums of length n and an integer array queries of length m. For each query, return the maximum size of a subsequence that can be selected from nums such that the sum of its elements is less than or equal to the query value. A subsequence is derived by deleting some or no elements from the array while keeping the relative order intact.

Leetcode 2391: Minimum Amount of Time to Collect Garbage

You are given an array of strings garbage where each string represents the garbage collected at a specific house. The characters ‘M’, ‘P’, and ‘G’ represent metal, paper, and glass garbage, respectively. The time to collect one unit of garbage is 1 minute. You are also given an array travel where each element represents the time required to travel between two consecutive houses. Three trucks are responsible for picking up different types of garbage and can only travel sequentially from house 0 to the end. Each truck only collects one type of garbage and each truck can only be used one at a time. Return the minimum time required to pick up all the garbage.

Leetcode 2406: Divide Intervals Into Minimum Number of Groups

You are given a 2D array of intervals, where each interval is represented as a pair of integers [left, right], denoting an inclusive range. Your task is to divide these intervals into the minimum number of groups such that no two intervals within the same group overlap. Two intervals overlap if there is at least one common number between them.

Leetcode 2420: Find All Good Indices

Given an integer array nums of size n and a positive integer k, find all good indices in the array. An index i is considered good if: The k elements just before it are in non-increasing order, and the k elements just after it are in non-decreasing order. Return a list of all good indices in increasing order.

Leetcode 2428: Maximum Sum of an Hourglass

You are given a matrix of integers. An hourglass is defined as a pattern of elements in the matrix where the middle element is surrounded by 3 elements above it and 3 elements below it, forming the shape of an hourglass. Your task is to find the maximum sum of all hourglasses that can be formed within the matrix.