22. Generate Parentheses[M] 问题 思路1——DP 思路2:回溯 22. Generate Parentheses[M] 问题 Given n pairs of parentheses, write a function to generate all combinations of well-formed par...
015. 3Sum 问题 思路 代码 015. 3Sum 问题 Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives ...
16. 3Sum Closest [M] 思路 代码 16. 3Sum Closest [M] Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the su...