LeetCode 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 toT.

Each number in C may only be used once in the combination.

Note:

All numbers (including target) will be positive integers.
Elements in a combination (a1, a2, … , ak) must be in non-descending order. (ie, a1 ≤ a2 ≤ … ≤ ak).
The solution set must not contain duplicate combinations.

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]

 1 public class Solution {
 2     List<List<Integer>> result;
 3     public List<List<Integer>> combinationSum2(int[] num, int target) {
 4         result = new ArrayList<List<Integer>>();
 5         List<Integer> list = new ArrayList<Integer>();
 6         Arrays.sort(num);
 7         combination(num, 0, list, target);
 8         return result;
 9     }
10     
11         void combination(int[] num,int index,List<Integer> curr,int target) {
12         if (target == 0) {
13             result.add(new ArrayList<Integer>(curr));
14 
15         } else {
16             for (int i = index; i < num.length; i++) {
17                 if (i != index && num[i] == num[i - 1]) {
18                     continue;
19                 }
20                 if (target >= num[i]) {
21                     curr.add(num[i]);
22                     combination(num, i + 1, curr, target - num[i]);
23                     curr.remove(curr.size() - 1);
24                 }
25             }
26         }
27 
28     }
29     
30 }