yys130826的博客

class Solution: def change(self, amount: int, coins: List[int]) -> int: dp=[0]*(amount+1) dp[0]=1 for i in range(len(coins)):#先遍历物品，再遍历背包。是求组合数。反之求排列数。 for j in range(coins[i],amount+1): dp[j]+=dp.