[leetcode] Combination Sum

debug了半天发现原来把index 当成i

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public class Solution { List<List<Integer>> result = new ArrayList<List<Integer>>(); public List<List<Integer>> combinationSum(int[] candidates, int target) { if (target <= 0 || candidates == null) return result; Arrays.sort(candidates); ArrayList<Integer> temp = new ArrayList<Integer>(); recur(candidates, 0, new ArrayList<Integer>(), target); return result; } private void recur(int []candidates, int index, List<Integer> fromPrev, int target){ if (index == candidates.length || target < 0) return; if (target == 0){ List<Integer> temp = new ArrayList<Integer>(fromPrev); result.add(temp); return; } for (int i = index; i < candidates.length; i++){ if (i < candidates.length-1 && candidates[i] == candidates[i+1]) i++; fromPrev.add(candidates[i]); recur(candidates, i, fromPrev, target-candidates[i]); fromPrev.remove(fromPrev.size()-1); } } }