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https://leetcode.com/problems/next-permutation/ Implement next permutation, which rearranges numbers into the lexicographically next greater permutati 阅读全文
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https://leetcode.com/problems/multiply-strings/ Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and n 阅读全文
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https://leetcode.com/problems/permutations-ii/ Given a collection of numbers that might contain duplicates, return all possible unique permutations. E 阅读全文
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https://leetcode.com/problems/permutations/ Given a collection of distinct integers, return all possible permutations. Example: 代码： 全排列 $dfs$ 写就好的啦 第一 阅读全文
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https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/ Given an array of integers nums sorted in ascending order, find 阅读全文
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https://leetcode.com/problems/4sum/ Given an array nums of n integers and an integer target, are there elements a, b, c, and d in nums such that a + b 阅读全文
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https://leetcode.com/problems/3sum-closest/ Given an array nums of n integers and an integer target, find three integers in nums such that the sum is 阅读全文
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https://leetcode.com/problems/3sum/ Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique tri 阅读全文
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https://leetcode.com/problems/trapping-rain-water/ Given n non-negative integers representing an elevation map where the width of each bar is 1, compu 阅读全文