Python 3:列表索引超出范围

Question

每次运行这个命令时，我都会遇到这样的错误：IndexError：list index out of range。

import random

cards = ['2', '2', '2', '2', '3', '3', '3', '3', '4', '4', '4', '4', '5', '5', '5', '5', '6', '6', '6', '6', '7', '7', '7', '7', '8', '8', '8', '8', '9', '9', '9', '9', '10', ',10', '10', '10', 'J', 'J', 'J', 'J', 'Q', 'Q', 'Q', 'Q', 'K', 'K', 'K', 'K', 'A', 'A', 'A', 'A']

randomness = 51

while True:

    cardIndex = random.randint(0, randomness)
    del cards[cardIndex]
    randomness = randomness -1
    print(cards[cardIndex])

Answer 1

按该索引删除前打印cards[cardIndex]：

while cards: # Because we need to stop somewhere
    cardIndex = random.randint(0, randomness)
    print(cards[cardIndex])
    del cards[cardIndex]
    randomness = randomness -1

而且你根本不需要randomness：

while cards:
    cardIndex = random.randrange(len(cards))
    print(cards[cardIndex])
    del cards[cardIndex]

您可以使用以下两种random.sample之一来完成此操作

for c in random.sample(cards, len(cards)):
    print(c)

或random.shuffle (将修改cards列表)：

random.shuffle(cards)
for c in cards:
    print(c)

Answer 2

您的问题是您首先删除卡片，然后打印它，所以问题是当您选择最后一张卡片时：

randomness = 51

while True:

    cardIndex = random.randint(0, randomness) #random.randint(0, 51) could give num 51 so card 52
    del cards[cardIndex] # deleted 52nd card (num 51)
    randomness = randomness -1
    print(cards[cardIndex]) # there is no 52nd card (num 51) anymore

您想要的是更改打印和删除：

while len(cards) > 0: # once yours pack of card is empty you want to stop
    cardIndex = random.randint(0, randomness)
    print(cards[cardIndex])
    del cards[cardIndex]
    randomness = randomness -1

len()告诉你有多少东西在列表中，它现在应该工作了:)

Answer 3

while cards:
    idx = random.randint(0, len(cards) - 1)
    print(cards[idx])
    del cards[idx]