import java.util.*; public class Solution { /** * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可 * * * @param nums int整型一维数组 * @param target int整型 * @return int整型 */ // ArrayList<ArrayList<Integer>> res = new ArrayList<ArrayList<Integer>>(); int res = 0; LinkedList<Integer> path = new LinkedList<Integer>(); public int combination (int[] nums, int target) { getCombine(target, nums); return res; } private void getCombine(int target, int[] nums) { if (target < 0) { return; } if (target == 0) { res++; return; } for (int i = 0; i < nums.length; ++i) { path.add(nums[i]); getCombine(target - nums[i], nums); path.removeLast(); } } }