Python词汇测试程序报错IndexError: list index out of range如何修复？

我是编程新手，正在用Python开发一款词汇测试程序。程序流程为：先录入自定义的瑞典语-英语词汇对，答题时将答错的词汇存入错题列表；重测错题时，若答对则需将该词汇从错题列表中移除，最终答对所有错题后列表应为空。但重测过程中出现报错：IndexError: list index out of range，请问该如何解决？（代码由其他语言翻译而来，可能存在不匹配情况）

import replit, sys, time, os
word = []
word1 = []
wordwrong = []
wordwrong1 = []
incorrect = 0
correct = 0
swedish = ""

print("Type: 'Stop' to stop")
while swedish.lower() != "stop":
  swedish = input("\nType the word in swedish:")
  if swedish.lower() != "stop":
    word.append(swedish)
  else:
    replit.clear()
    break
  english = input("\nType the word in english:")
  word1.append(english)
  replit.clear()
  print("Type: 'Stop' to stop")

for x in range(len(word)):
  wordanswer = input("translate word " + "'" + word[x] + "'" + ":").lower()
  replit.clear()
  while wordanswer != word1[x]:
    print("Incorrect answer! try again, " + str(2-incorrect) + " tries left")
    wordanswer = input("translate " + "'" + word[x] + "'" + ":")
    incorrect = incorrect + 1
    replit.clear()
    if incorrect == 2:
      replit.clear()
      incorrect = incorrect-2
      wordwrong.append(word[x])
      wordwrong1.append(word1[x])        
      break
  else:
    print("Correct answer!")
    correct = correct + 1
    incorrect = incorrect*0
replit.clear()

print("Your result:", correct, "/", len(word), "correct answers " +"(" + str(correct/len(word)*100)+"%)")


restart = input("\nTo restart; type 'restart':").lower()

correct = correct*0
incorrect = incorrect*0



restart = "restart"
while restart == "restart" and len(wordwrong) > 0:
  for x in range(len(wordwrong)):
    wordanswer = input("translate word " + "'" + wordwrong[x] + "'" + ":").lower()
    
    while wordanswer != wordwrong[x]:
      print("Incorrect answer! try again, " + str(2-incorrect) + " tries left")
      wordanswer = input("translate word " + "'" + wordwrong[x] + "'" + ":")
      incorrect = incorrect + 1
      
      if incorrect == 2:
        incorrect = incorrect-2
        break
    else:
      print("Correct answer!")
      correct = correct + 1
      incorrect = incorrect*0
      wordwrong.remove(wordwrong[x])
      wordwrong1.remove(wordwrong1[x])     (here i am trying to remove the words that got corrected)
      
  
print("Your result:", correct, "/", len(word), "correct answers " +"(" + str(correct/len(word)*100)+"%)")
   
  
  restart = input("\nTo restart; type 'restart':").lower()

问题原因 #

报错的核心是遍历列表时直接修改列表长度：

• 重测阶段用for x in range(len(wordwrong))循环，循环次数基于列表初始长度。
• 当执行wordwrong.remove(wordwrong[x])时，列表长度会缩短，但循环的x仍按初始长度递增，当x超过修改后的列表最大索引时，就会触发IndexError。
• 另外还存在逻辑错误：重测时判断答案的条件写成了wordanswer != wordwrong[x]，实际应该拿输入的英语和wordwrong1[x]（对应英语翻译）对比，否则永远判断错误。

解决方案 #

1. 反向遍历列表 #

从列表最后一个元素往前遍历，这样即使前面的元素被移除，后续循环的索引不会越界。修改重测阶段的循环：

# 替换原for循环
for x in range(len(wordwrong)-1, -1, -1):

2. 修正答案判断逻辑 #

把重测时的while wordanswer != wordwrong[x]改成：

while wordanswer != wordwrong1[x].lower():

3. 修正其他细节 #

• 移除代码里的注释括号(here i am trying to remove the words that got corrected)，避免语法错误。
• 重测结束后的restart输入缩进错误，调整到循环内。

修正后的完整代码 #

import replit, sys, time, os
word = []
word1 = []
wordwrong = []
wordwrong1 = []
incorrect = 0
correct = 0
swedish = ""

print("Type: 'Stop' to stop")
while swedish.lower() != "stop":
  swedish = input("\nType the word in swedish:")
  if swedish.lower() != "stop":
    word.append(swedish)
  else:
    replit.clear()
    break
  english = input("\nType the word in english:")
  word1.append(english)
  replit.clear()
  print("Type: 'Stop' to stop")

for x in range(len(word)):
  wordanswer = input("translate word " + "'" + word[x] + "'" + ":").lower()
  replit.clear()
  while wordanswer != word1[x].lower():
    print("Incorrect answer! try again, " + str(2-incorrect) + " tries left")
    wordanswer = input("translate " + "'" + word[x] + "'" + ":").lower()
    incorrect = incorrect + 1
    replit.clear()
    if incorrect == 2:
      replit.clear()
      incorrect = incorrect - 2
      wordwrong.append(word[x])
      wordwrong1.append(word1[x])        
      break
  else:
    print("Correct answer!")
    correct = correct + 1
    incorrect = 0
replit.clear()

print("Your result:", correct, "/", len(word), "correct answers " +"(" + str(round(correct/len(word)*100, 2))+"%)")


restart = input("\nTo restart; type 'restart':").lower()

correct = 0
incorrect = 0


while restart == "restart" and len(wordwrong) > 0:
  # 反向遍历避免索引越界
  for x in range(len(wordwrong)-1, -1, -1):
    wordanswer = input("translate word " + "'" + wordwrong[x] + "'" + ":").lower()
    
    while wordanswer != wordwrong1[x].lower():
      print("Incorrect answer! try again, " + str(2-incorrect) + " tries left")
      wordanswer = input("translate " + "'" + wordwrong[x] + "'" + ":").lower()
      incorrect = incorrect + 1
      
      if incorrect == 2:
        incorrect = incorrect - 2
        break
    else:
      print("Correct answer!")
      correct = correct + 1
      incorrect = 0
      # 移除答对的错题
      wordwrong.pop(x)
      wordwrong1.pop(x)
  
  replit.clear()
  print("Your result:", correct, "/", len(wordwrong)+correct, "correct answers " +"(" + str(round(correct/(len(wordwrong)+correct)*100, 2))+"%)")
   
  restart = input("\nTo restart; type 'restart':").lower()

内容的提问来源于stack exchange，提问作者Maxx2774