算法练习Day43|● 518. 零钱兑换 II ● 377. 组合总和 Ⅳ

 1class Solution {
 2    public int change(int amount, int[] coins) {
 3
 4        int[] dp = new int[amount + 1];
 5        dp[0] = 1;
 6
 7        for (int i = 0; i < coins.length; i++) {
 8            for (int j = coins[i]; j <= amount; j++) {
 9                dp[j] += dp[j - coins[i]];
10            }
11        }
12        return dp[amount];
13    }
14}

 1class Solution {
 2    public int combinationSum4(int[] nums, int target) {
 3        int[] dp = new int[target + 1];
 4        dp[0] = 1;
 5
 6        for (int i = 0; i <= target; i++) {
 7            for (int j = 0; j < nums.length; j++) {
 8                if (i >= nums[j]) {
 9                    dp[i] += dp[i - nums[j]];
10                }
11            }
12        }
13        return dp[target];
14    }
15}