322.LeetCode硬幣找零

題目描述：

初始化：inf，dp[0] = 0

採用方法：動態規劃

參考地址：https://www.cnblogs.com/grandyang/p/5138186.html

coins = [1, 2, 5]
amount = 11

#dp[i]:面值爲i時需要的最少硬幣數量
dp = [float("inf")] * (amount + 1)
dp[0] = 0
for i in range(amount + 1):
    for j in range(len(coins)):
        if coins[j] <= i:
            dp[i] = min(dp[i], dp[i-coins[j]]+1)
print(dp[amount] if dp[amount] <= amount else -1)