Method backtrack

39-combination-sum/combination-sum.java:12–24

(List<List<Integer>> result, List<Integer> temp, int[] candidates, int remain, int start)

    }
    
    private void backtrack(List<List<Integer>> result, List<Integer> temp, int[] candidates, int remain, int start) {
        if (remain < 0) return;
        if (remain == 0) {
            result.add(new ArrayList<>(temp));
            return;
        }
        
        for (int i = start; i < candidates.length; i++) {
            temp.add(candidates[i]);
            backtrack(result, temp, candidates, remain - candidates[i], i);
            temp.remove(temp.size() - 1);
        }
    }
}