Determine if an input string matches a given regular expression that supports '.' and '*' characters. The '.' matches any single character, and '*' matches zero or more occurrences of the preceding element.

Given a string of digits, remove *k* digits to obtain the smallest possible number. You need to determine which digits to remove to minimize the resulting number.

You have K sorted lists of numbers. Find the smallest range [min, max] that includes at least one number from each of the K lists.

You are given a list of candies with different tastiness values. Choose a candy basket such that the minimum tastiness difference between any two candies in the basket is maximized.

Simulate a simple bank system that supports basic operations like deposit, withdraw, and check balance for different accounts. You will implement methods to handle these transactions and ensure validity based on account balances and existence.

You're given a string and a list of index pairs. You can swap characters at these indices any number of times. Find the lexicographically smallest string you can obtain after performing these swaps.

A robot collects money from houses on a street, but an alarm will sound if it robs two adjacent ones. Given the amounts of money in each house, find the maximum total amount the robot can collect without setting off the alarm.

Given a large sequence and a smaller subsequence, find all the shortest supersequences that contain the subsequence. Return the frequencies of each unique character within these shortest supersequences.

You start at a point on an infinite grid and can move to adjacent coordinates or double your current coordinates. Determine if you can reach a given target point using these moves.

You're given a string and two patterns. Find all 'beautiful' indices where an occurrence of the first pattern is within 'k' distance of an occurrence of the second pattern.

Determine how many arrays of a specific length can be formed where exactly 'k' pairs of adjacent elements are identical. The array elements must be within a defined range.

Given an array representing the height of bars, calculate how much water can be trapped between them after rain. Think about finding the maximum height to the left and right of each bar.

You're given an array representing bloom days for flowers. Find the minimum number of days needed to create a certain number of bouquets, given each bouquet needs a specific number of adjacent flowers.

Find the longest palindromic substring within a given string. A palindromic substring reads the same forwards and backward.

Imagine stones on a grid. You can remove stones if they share a row or column with another stone. Find the maximum number of stones you can remove.

You're given a list of jobs with start times, end times, and profits. Find the maximum profit you can obtain by scheduling a subset of jobs that don't overlap.

You are a robber planning to rob houses along a street. Maximize your loot, but be careful - adjacent houses have connected security systems that will trigger an alarm if you rob them both.

Imagine a tree structure where each node represents a city. Calculate the sum of distances from each city to all other cities in the tree.

You are given an array where each element represents the maximum jump length from that position. Find the minimum number of jumps required to reach the last index.

Imagine you're planning a trip using a network of bus routes. Given a set of routes and start/end locations, find the fewest number of buses you must take to reach your destination.