Question

我正在尝试制作一个遍历列表中所有项目的代码：

def lunch():
global tl
print("You have %s minutes until school starts." % (tl))
go=True
lunch=["pasta","pb+j","chicken","cheez its","goldfish","pirate's booty","cookie","cupcake","gogurt","strawberries","apple","grapes","carrots","bell peppers","pea pods"]
a=0
while a<len(lunch)-4:
    print("Do you pack or buy your lunch? (p,b)")
    lunch=input()
    if lunch=="pack" or lunch=="p":
        go2=True
        while go2:
            print("Do you want %s, %s, or %s?" % (lunch[a],lunch[a+1],lunch[a+2]))
            l=input()
            if not(l==lunch[a] or l==lunch[a+1] or l==lunch[a+2]):
                print("What?")
            else:
                print("Yay!")
                go2=False
        a+=3

但我不断收到错误“”IndexError：字符串索引超出范围“

print("Do you want %s, %s, or %s?" % (lunch[a],lunch[a+1],lunch[a+2]))

我知道这意味着索引大于或小于它可以索引的索引（大于或小于列表长度减去1），但它不应该这样做，因为它从零开始并结束列表结束前的四个。

Answer 1

问题在于我覆盖了变量public void draw(Graphics2d g2)，就像Aiven所说的那样。感谢

Answer 2

您的问题是lunch[a+n]中对索引的引用超出范围。您可以代表您的选择。

lunch = ['pasta', 'pudding', 'cereal', 'steak']

print('Would you like {0} or {1} or {2} or {3}'.format(*lunch))

Python错误“IndexError：字符串索引超出范围”

2 个答案: