摘要：
Find all possible combinations ofknumbers that add up to a numbern, given that only numbers from 1 to 9 can be used and each combination should be a u... 阅读全文
摘要：
Given a collection of candidate numbers (C) and a target number (T), find all unique combinations inCwhere the candidate numbers sums toT.Each number ... 阅读全文
摘要：
Given a set of distinct integers,nums, return all possible subsets.Note:Elements in a subset must be in non-descending order.The solution set must not... 阅读全文
摘要：
Given a set of candidate numbers (C) and a target number (T), find all unique combinations inCwhere the candidate numbers sums toT.Thesamerepeated num... 阅读全文
摘要：
Givenn, generate all structurally uniqueBST's(binary search trees) that store values 1...n.For example,Givenn= 3, your program should return all 5 uni... 阅读全文