Combination Sum II
Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T.
Each number in C may only be used once in the combination.
Note:
For example, given candidate set 10,1,2,7,6,1,5
and target 8
,
A solution set is:
[1, 7]
[1, 2, 5]
[2, 6]
[1, 1, 6]
分析:
跟前面的题很相似,给定的candidates中有重复的数,并且每个数只能使用一次。在上一题的代码中稍作修改即可。
代码:
class Solution(object): def combinationSum2(self, candidates, target): """ :type candidates: List[int] :type target: int :rtype: List[List[int]] """ solutions = [] candidates.sort() self.dfs(candidates, target, 0, len(candidates) - 1, list(), solutions) return solutions def dfs(self, candidates, gap, start, end, knums, solutions): if gap == 0: if knums not in solutions: solutions.append(knums) return i = start while i <= end: if gap < candidates[i]: return self.dfs(candidates, gap - candidates[i], i + 1, end, knums + [candidates[i]], solutions) i += 1