與 39. Combination Sum不同的是不能重複取

class Solution(object):
    def combinationSum2(self, candidates, target):
        """
        :type candidates: List[int]
        :type target: int
        :rtype: List[List[int]]
        """
        
        res=[]
        def dfs(cans,index,target,path):
            if
 
 target==0:
                res.append(path) 
            if target<0:
                return
            for i in range(index,len(cans)):
                if i!=index and cans[i]==cans[i-1]:
                    continue 
                dfs(cans,i+1,target-cans[i],path+[cans[i]])
        candidates.
 
sort()
        dfs(candidates,0,target,[])
        return res