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Leetcode 2938: Separate Black and White Balls

You are given a binary string s of length n, where each character represents a ball: ‘1’ for black and ‘0’ for white. The goal is to arrange the balls such that all the white balls are on the left side and all the black balls are on the right side, by swapping two adjacent balls in each step. You need to find the minimum number of adjacent swaps required to achieve this arrangement.

Leetcode 2942: Find Words Containing Character

You have n balls placed on a table, each either black or white, represented by a binary string s. In each move, you can swap two adjacent balls. Your task is to determine the minimum number of swaps required to move all black balls to the right side and all white balls to the left side.

Leetcode 2947: Count Beautiful Substrings I

You are given a string s and a positive integer k. A string is beautiful if it satisfies the conditions that the number of vowels equals the number of consonants, and the product of the number of vowels and consonants is divisible by k. Return the number of non-empty beautiful substrings in the string.

Leetcode 2957: Remove Adjacent Almost-Equal Characters

You are given a 0-indexed string word. In each operation, you can change any character of word to a lowercase English letter. Two characters are considered almost-equal if they are the same or adjacent in the alphabet. Your task is to remove all adjacent almost-equal characters with the minimum number of operations.

Leetcode 3042: Count Prefix and Suffix Pairs I

You are given a 0-indexed string array words. You need to determine the number of index pairs (i, j) such that i < j and the string at index i is both a prefix and a suffix of the string at index j. The function isPrefixAndSuffix(str1, str2) returns true if str1 is both a prefix and a suffix of str2, and false otherwise.

Leetcode 3043: Find the Length of the Longest Common Prefix

You are given two arrays arr1 and arr2 containing positive integers. Your task is to find the length of the longest common prefix between all pairs of integers (x, y) such that x belongs to arr1 and y belongs to arr2. A prefix of a number is any integer formed by one or more digits starting from its leftmost digit. For example, 123 is a prefix of 12345, but 234 is not. If no common prefix exists for any pair, return 0.