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Given a nonempty array of integers, every element appears twice except for one. Find that single one. Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? Examples: Input: [2,2,1] Output: 1 Input: [4,1,2,1,2] Output: 4
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.\n\n Constraints:\n 1 <= strs.length <= 10^4\n 0
Given two strings s and t, determine if t is an anagram of s. 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 <= s.length, t.length <= 5 10^4 s and t consist of lowercase English lett
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Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. You may assume that each input would have exactly one solution, and you may not use the same element twice. The order of the returned indices does not matter. Constraints: 2 <= n