1 public class Solution { 2 public ArrayList<ArrayList<Integer>> combinationSum2(int[] num, int target) { 3 // IMPORTANT: Please reset any member data you declared, as 4 // the same Solution instance will be reused for each test case. 5 HashSet<ArrayList<Integer>> result = new HashSet<ArrayList<Integer>>(); 6 ArrayList<ArrayList<Integer>> finalresult = new ArrayList<ArrayList<Integer>>(); 7 ArrayList<Integer> output = new ArrayList<Integer>(); 8 int sum = 0; 9 int len = num.length, depth = 0; 10 if(len == 0){ 11 return finalresult; 12 } 13 Arrays.sort(num); 14 generate(result, output, sum, depth, len, target, num); 15 finalresult.addAll(result); 16 return finalresult; 17 } 18 19 public void generate(HashSet<ArrayList<Integer>> result, ArrayList<Integer> output, int sum, 20 int depth, int len, int target, int[] candidates){ 21 if(sum > target){ 22 return; 23 } 24 if(sum == target){ 25 ArrayList<Integer> tmp = new ArrayList<Integer>(); 26 tmp.addAll(output); 27 result.add(tmp); 28 return; 29 } 30 31 for(int i = depth; i < len; i++){ 32 sum += candidates[i]; 33 output.add(candidates[i]); 34 generate(result, output, sum, i+1, len, target, candidates); 35 sum -= output.get(output.size() - 1); 36 output.remove(output.size() - 1); 37 } 38 } 39 }
