Python列表输入2个相同的单词，如何只打印一次

Question

嗨，第一次在这里发帖，我正在尝试制作一个仅打印一次输入的列表。 例如，如果用户输入：car dog dog house car 那么你的程序应该显示：car dog house

wordlist = []
while True:
  word  = (input("Enter a word (blank to quit): "))
  wordlist.append(word)
  if word == wordlist:
   wordlist.remove(word)
  if word == "":
     break

for word in wordlist:
    print(word)

我也试过

if word == wordlist:
    wordlist[-1]

任何帮助都会很棒。

Answer 1

如果单词顺序无关紧要，请使用set

wordlist = set()
while True:
    word  = (input("Enter a word (blank to quit): "))
    if word == "":
        break
    wordlist.add(word)

for word in wordlist:
    print(word)

如果插入单词的顺序很重要，请附加带有条件的列表

wordlist = []
while True:
    word  = (input("Enter a word (blank to quit): "))
    if word == "":
        break
    if word not in wordlist:
        wordlist.append(word)

for word in wordlist:
    print(word)

如果您想保留重复项但只想在打印时删除

for word in set(wordlist):
    print(word)

如果在打印时需要维护订单

visited=set()
for word in wordlist:
    if word not in visited:
        print(word)
        visited.add(word)

Answer 2

In [49]: words = 'car dog dog house car'.split()                                           

In [50]: from collections import OrderedDict                                               

In [51]: word_dict = OrderedDict()                                                         

In [52]: for word in words: 
    ...:     word_dict[word] = None 
    ...:                                                                                   

In [53]: for word in word_dict: 
    ...:     print(word) 
    ...:                                                                                   
car
dog
house

Answer 3

您可以尝试以下操作：

wordlist = []
while True:
  word  = (input("Enter a word (blank to quit): "))
  if not word:
    break
  elif word not in wordlist:
    wordlist.append(word)

for word in wordlist:
    print(word)