货币找零

class Solution(object):
    def coinChange(self, coins, amount):
        """
        :type coins: List[int]
        :type amount: int
        :rtype: int
        """
        n = len(coins)
        # dp[i]表示amount=i需要的最少coin数
        dp = [float("inf")] * (amount+1)
        dp[0] = 0
        for i in range(amount+1):
            for j in range(n):
                # 只有当硬币面额不大于要求面额数时，才能取该硬币
                if coins[j] <= i:
                    dp[i] = min(dp[i], dp[i-coins[j]]+1)
        # 硬币数不会超过要求总面额数，如果超过，说明没有方案可凑到目标值
        return dp[amount] if dp[amount] <= amount else -1

来源：CSDN

作者：ailinyingai

链接：https://blog.csdn.net/ailinyingai/article/details/104030940