377.组合总和-ⅳ.java

/*
 * @lc app=leetcode.cn id=377 lang=java
 *
 * [377] 组合总和 Ⅳ
 */

// @lc code=start
class Solution {
    public int combinationSum4(int[] nums, int target) {
        int[] dp = new int[target + 1];
        dp[0] = 1;
        for (int i = 1; i < dp.length; i++) {
            for (int j = 0; j < nums.length; j++) {
                if (nums[j] <= i) {
                    dp[i] += dp[i - nums[j]];
                }
            }
        }

        return dp[target];
    }
}
// @lc code=end