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Given a nonempty array of integers nums, every element appears twice except for one. Find that single one. Constraints: The array nums is nonempty. Each element in the array appears twice, except for one element which appears only once. Example: Input: nums = [2,2,1] Output: 1 Another Example: Input
You are given the heads of two sorted linked lists, list1 and list2. Merge the two lists into one sorted list. The list should be made by splicing together the nodes of the first two lists. Return the head of the merged linked list. Constraints: The number of nodes in both lists is in the range [0,
You are given a large integer represented as an integer array digits, where each digits[i] is the ith digit of the integer. The digits are ordered from most significant to least significant in lefttoright order. The large integer does not contain any leading zeros, except for the number 0 itself. In
Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must be unique, and you may return the result in any order. Constraints: 1 <= nums1.length, nums2.length <= 1000 0 <= nums1[i], nums2[i] <= 1000 Example: Input: nums1 = [1,2,2,1], nums2 = [2,2
Given a sorted array nums, remove the duplicates inplace such that each unique element appears only once. The relative order of the elements should be kept the same. Your function should return the new length k after removing the duplicates. Do not allocate extra space for another array; you must do
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:
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