Question

好吧，这是我写过的最长的代码，所以如果它有点乱，我道歉。第一次计算机科学任务。

def main():

#generate random value
import random
rand = random.randint(1, 99)


#instructions
print("""The purpose of this exercise is to enter a number of coin values
that add up to a displayed target value. Enter coins as 1=penny, 5-nickel, 
10-dime, 25-quarter. Hit return after the last entered coin value.""")



#defining function for 'first coin'
def firstCoin ():
    coins = []
    global coins
    coin = int(input("Enter first coin: "))
    if coin > rand:
        print("Sorry, total value exceeds", rand, "cents.")
        again = input("Try again (y/n): ")
        if again == "y" or "Y":
            main()
        else:
            sys.exit() #ends program
    elif coin in possible:
        coins.append(coin)
        nextCoinplease()



#defining function for 'next coin'
def nextCoinplease ():
    while True:         
        nextcoin = (input("Enter next coin: "))
        if nextcoin in possible:
            coins.append(nextcoin)
        elif nextcoin == "":
            break
    else: print("Invalid entry.")


#making lists
possible = [1, 5, 10, 25]
print("Enter coins that add up to", rand, "cents, one per line.") #program start
firstCoin ()


sumcoin = sum(coins)
print(sumcoin)
if sumcoin == rand:
    print("Correct!")
else: 
    print("Invalid entry.")
    firstCoin()

main()

所以，这是我的问题。由于某种原因，函数nextCoinplease中的用户输入不会被添加到列表＆＃34; coins＆＃34;，只有函数firstCoin的第一个输入。这意味着总和（硬币）实际上只是第一个输入。我不能为我的生活找出原因，所以任何意见都会非常感激，谢谢！

Answer 1

您有两个input语句，一个用于获取coin，另一个用于获取nextcoin。它们是不同的。有什么区别？

^{（我故意不直接给出答案，因为从你到目前为止所写的内容来看，我相信你可以根据这个暗示来解决这个问题。）}

Answer 2

input的返回类型是一个字符串，因此nextcoin in possible总是失败，因为possible只包含整数。尝试使用int()将输入解析为整数。

Answer 3

您的代码永远不会检查rand是否等于sumCoin，因此它永远不会停止。我已修复此问题，此代码现在可以使用。

repl.it

上的演示

我做了什么？

我移动了if语句，该语句在rand == sumCoin的{{1}}循环开头检查while是否为nextCoinPlease()，以便检查sumCoin值在输入每个下一个硬币值之前，一旦它等于rand就会停止。

代码：

import random
import sys


def main():

    rand = random.randint(1, 99)

    print('''The purpose of this exercise is to enter a number of coin values \
          that add up to a displayed target value. Enter coins as 1=penny, \
          5=nickel, 10-dime, 25-quarter. Hit return after the last entered \
          coin value.''')
    coins = []

    def firstCoin():
        coin = int(input("Enter first coin: "))
        if coin > rand:
            print('Sorry, total value exceeds ', rand, ' cents.')
            again = input('Try again? (y/n): ')
            if again == 'y' or 'Y':
                main()
            else:
                sys.exit()
        elif coin in possible:
            coins.append(coin)
            nextCoinPlease()

    def nextCoinPlease():
        while True:
            sumCoin = sum(coins)
            print('Total Value: ' + str(sumCoin))
            print ''
            if sumCoin == rand:
                print('Correct! You Win!')
                sys.exit()
            elif sumCoin > rand:
                print('You exceeded the total value! You lose! Try again!')
                sys.exit()
            nextCoin = (input('Enter next coin: '))
            if nextCoin in possible:
                coins.append(nextCoin)
            elif nextCoin == "":
                break
            else:
                print('Invalid entry.')

    possible = [1, 5, 10, 25]
    print('Enter coins that add up to', rand, 'cents, one per line.')
    firstCoin()

main()

（超级初学者）有人可以解释我的名单出了什么问题吗？

3 个答案:

repl.it

我做了什么？

代码：