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Write a function to find the longest common prefix string amongst an array of strings. If there is no common prefix, return an empty string "". All given inputs are lowercase English letters az. The number of strings n will be between 0 and 200. The length of each string will be between 0 and 200. E
Given an array of strings strs, group the anagrams together. You can return the answer in any order. An anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once. Constraints: 1 <= strs.length <= 10^4 0 <= strs[
You are given an array prices where prices[i] is the price of a given stock on the ith day. You want to maximize your profit by choosing a single day to buy one stock and choosing a different day in the future to sell that stock. Return the maximum profit you can achieve from this transaction. If yo
Given an integer array nums, determine if it contains any duplicates. Return true if any value appears at least twice in the array, and return false if every element is distinct. Constraints: 1 <= nums.length <= 10^5 10^9 <= nums[i] <= 10^9 Example: Input: nums = [1,2,3,1] Output: true Explanation:
Given an input string s, reverse the order of the words. Constraints: A word is defined as a sequence of nonspace characters. Words are separated by at least one space. The input string may contain leading or trailing spaces. Multiple spaces between two words should be reduced to a single space in t
You are given an array nums containing n distinct numbers in the range [0, n]. Your task is to find and return the only number in the range that is missing from the array. n is the length of nums. 1 <= n <= 10^4 0 <= nums[i] <= n All numbers in nums are unique. Example 1: Input: nums = [3,0,1] Outpu
A palindrome is a sequence of characters that reads the same forwards and backwards. Given a string s, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example: Input: s = "A man, a plan, a canal: Panama" Output: true Explanation: "amanaplanacanalpana
Given a string s containing just the characters (, ), {, }, [, ], determine if the input string is valid. A string is valid if: Open brackets must be closed by the same type of brackets. Open brackets must be closed in the correct order. Every close bracket has a corresponding open bracket of the sa
Given an integer array nums, rotate the array to the right by k steps, where k is nonnegative. You must do this inplace with O(1) extra space. Constraints: 1 <= nums.length <= 10^5 2^31 <= nums[i] <= 2^31 1 0 <= k <= 10^5 Example: Input: nums = [1,2,3,4,5,6,7], k = 3 Output: [5,6,7,1,2,3,4] Explanat
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