python学习之找零问题(递归和动态规划两种解法)

Posted 2021-07-14 今夜月色很美

递归解决找零问题

def recMC(coinList, change):
    minCoins = dic.get(change)
    if minCoins:
        return minCoins
    print("========%s"%change)
    minCoins = change
    if change in coinList:
        minCoins = 1
    else:
        for j in [i for i in coinList if i < change]:
            res = recMC(coinList, change - j) + 1
            if minCoins > res:
                minCoins = res
    dic[change] = minCoins
    return minCoins


dic = {}
print(recMC([1,2,5,10,20,50,100], 342))

动态规划算法解决找零问题

def dynamic_change(coinList, change):
    for a in range(1, change + 1):
        if a in coinList:
            dic[a] = 1
        else:
            minCoins = a
            for j in [i for i in coinList if i < a]:
                if minCoins > dic[a - j] + 1:
                    dic[a] = dic[a - j] + 1


dic = {}
dynamic_change([1,2,5,10,20,50,100], 342)
print(dic[342])