Python:IndexError:列表索引超出范围仅在某些情况下发生

Question

我一直在做一个井字游戏的程序，需要两个玩家轮流输入棋盘坐标，比如 (r1,c1)->(r2,c2)-> (r3,c3)-> …，其中 r 是行，c 是列，棋盘看起来像

0 1 2
3 4 5
6 7 8

我输入的程序:

board=[0,1,2,3,4,5,6,7,8]
def show():
    print(str(board[0])+str(board[1])+str(board[2]))
    print(str(board[3])+str(board[4])+str(board[5]))
    print(str(board[6])+str(board[7])+str(board[8]))
def check(char,spot1,spot2,spot3):
    if board[spot1]==char and board[spot2]==char and board[spot3]==char:
        return True
def checkAll(char):
    if check(char,0,1,2):
        return True
    if check(char,3,4,5):
        return True
    if check(char,6,7,8):
        return True
    if check(char,0,3,6):
        return True
    if check(char,1,4,7):
        return True
    if check(char,2,5,8):
        return True
    if check(char,0,4,8):
        return True
    if check(char,2,4,6):
        return True
    else:
        return False
def ChangeSpotInputToAList(spotInput):
    spotafter=[]
    for i in spotInput:
        if i=="(0,0)":
            spotafter.append(0)
        if i=="(0,1)":
            spotafter.append(1)
        if i=="(0,2)":
            spotafter.append(2)
        if i=="(1,0)":
            spotafter.append(3)
        if i=="(1,1)":
            spotafter.append(4)
        if i=="(1,2)":
            spotafter.append(5)
        if i=="(2,0)":
            spotafter.append(6)
        if i=="(2,1)":
            spotafter.append(7)
        if i=="(2,2)":
            spotafter.append(8)
    return spotafter
i=0
spotInput=input().split("->")
spotafter=ChangeSpotInputToAList(spotInput)
for x in spotafter:
    show()
    if spotafter[x]%2==0:
        print("X-->",x)
        spot=x
        i+=1
        char="X"
        board[spot]=char
        if i==9:
            show()
            print("Winner: None")
            break
        if checkAll(char):
            show()
            print("Winner:",char)
            break
    if spotafter[x]%2==1:
        print("O-->",x)
        spot=x
        i+=1
        char="O"
        board[spot]=char
        if i==9:
            show()
            print("Winner: None")
            break
        if checkAll(char):
            show()
            print("Winner:",char)
            break

我尝试了一些输入，但其中一个一直出错，即 (2,2)->(0,0)->(1,1)->(0,2)-> (1,0)->(0,1)，程序显示:

012
345
678
Traceback (most recent call last):
  File "thisishardlol.py", line 55, in <module>
    if spotafter[x]%2==0:
IndexError: list index out of range
Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 63, in apport_excepthook
    from apport.fileutils import likely_packaged, get_recent_crashes
  File "/usr/lib/python3/dist-packages/apport/__init__.py", line 5, in <module>
    from apport.report import Report
  File "/usr/lib/python3/dist-packages/apport/report.py", line 30, in <module>
    import apport.fileutils
  File "/usr/lib/python3/dist-packages/apport/fileutils.py", line 23, in <module>
    from apport.packaging_impl import impl as packaging
  File "/usr/lib/python3/dist-packages/apport/packaging_impl.py", line 24, in <module>
    import apt
  File "/usr/lib/python3/dist-packages/apt/__init__.py", line 23, in <module>
    import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'

Original exception was:
Traceback (most recent call last):
  File "thisishardlol.py", line 55, in <module>
    if spotafter[x]%2==0:
IndexError: list index out of range

有谁知道我哪里错了吗？任何帮助将不胜感激!

Answer 1

让我们来看一个场景。

spotInput=input().split("->")
spotafter=ChangeSpotInputToAList(spotInput)

如果我输入 (2,2)->(2,2) 然后 spotafter = [8,8]

现在我进入我的 for 循环:

for x in spotafter:
    show()
    if spotafter[x]%2==0:

在我的第一个循环 x = 8 中，我试图获取 spotafter[8]，它不存在(spotafter 只有 2 个元素).

因为我不知道您的目标，所以我帮不上什么忙，但这就是您收到 IndexError 的原因。