Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.
Given an array of integers nums sorted in non-decreasing order, find the starting and ending position of a given target value. If target is not found in the array, return [-1, -1].
Implement pow(x, n), which calculates x raised to the power n.
Given an array of strings strs, group the anagrams together. You can return the answer in any order.
You are given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise).
Given a collection of numbers, nums, that might contain duplicates, return all possible unique permutations in any order.
You are given a 0-indexed array of integers nums of length n. You are initially positioned at nums. Each element nums[i] represents the maximum length of a forward jump from index i. In other words, if you are at nums[i], you can jump to any nums[i + j] where: 0 <= j <= nums[i] and i + j < n. Return the minimum number of jumps to reach nums[n - 1].
Given an input string (s) and a pattern (p), implement wildcard pattern matching with support for ‘?’ and ‘*’ where: ‘?’ Matches any single character.’*’ Matches any sequence of characters (including the empty sequence).The matching should cover the entire input string.
Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and num2, also represented as a string.
Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap after raining.
Given an unsorted integer array nums, return the smallest missing positive integer.
Given a collection of candidate numbers (candidates) and a target number (target), find all unique combinations in candidates where the candidate numbers sum to target.
Given an array of distinct integers candidates and a target integer target, return a list of all unique combinations of candidates where the chosen numbers sum to target. You may return the combinations in any order.
Given a linked list, swap every two adjacent nodes and return its head. You must solve the problem without modifying the values in the list’s nodes.
Given a string containing just the characters ‘(‘ and ‘)’, return the length of the longest valid (well-formed) parentheses substring.