Question

我的计划的目的是告诉用户他输入的单词的位置在哪里，例如，问你的国家可以做什么，因为你问你可以为你的国家做什么 “国家”一词出现在第5和第17位。

我的程序只打印第一个位置两次。我希望能得到一些帮助。

 Sentence = "the quick brown fox jumped over the lazy dog"
print (Sentence)
Sentence = Sentence.split()
while True:
    findword = input("Please enter the word to find: ")
    if not findword.isalpha() or len (findword)<3:
        print("Invalid") 
    break

for x in Sentence:
    if x==findword:
        Position = Sentence.index(findword)
        print(Position)

Answer 1

试试这个......

第一次出现在x

中的第一次出现的

s.index(x) - index

Sentence = "the quick brown fox jumped over the lazy dog"
print (Sentence)
Sentence = Sentence.split()
i=0
while True:
    findword = input("Please enter the word to find: ")
    if not findword.isalpha() or len (findword)<3:
        print("Invalid") 
    break

for x in Sentence:

    if x==findword:
        Position = Sentence.index(findword, i)
        print(Position)
    i=i+1;

Answer 2

在索引中，您需要指定开始搜索的起始索引，否则它将始终返回第一个匹配的索引。

prevPosition = 0

for x in Sentence:
    if x==findword:
        Position = Sentence.index(findword, prevPosition)
        prevPosition = Position + 1
        print(Position)

示例：

>>> Sentence
['the', 'quick', 'brown', 'fox', 'jumped', 'over', 'the', 'lazy', 'dog']
>>> findword = "the"
>>> prevPosition = 0
>>> 

>>> for x in Sentence:
...     if x==findword:
...         Position = Sentence.index(findword, prevPosition)
...         prevPosition = Position + 1
...         print(Position)
... 
0
6

Answer 3

这是一个与您的输入和预期输出（第5和第17位）匹配的解决方案

Sentence = "ASK NOT WHAT YOUR COUNTRY CAN DO FOR YOU ASK WHAT YOU CAN DO FOR YOUR COUNTRY"
print(Sentence)
Sentence = Sentence.split()
while True:
    findword = input("Please enter the word to find: ")
    if not findword.isalpha() or len(findword) < 3:
        print("Invalid")
    break

curr_position = 0

for x in Sentence:
    if x == findword:
        Position = Sentence.index(findword, curr_position + 1)
        curr_position = Position
        print(Position + 1)

Answer 4

这是for loop

的更改

for x in range(len(Sentence)):
    if Sentence[x]==findword:
        Position = x
        print(Position)

Answer 5

试试这段代码 -

Sentence = "the quick brown fox jumped over the lazy dog"
Sentence = Sentence.split()
print (Sentence)

findword = input("Please enter the word to find: ")
if not findword.isalpha() or len (findword)<3:
    print("Invalid") 

for wordIndex, x in enumerate(Sentence):
    if x == findword:
        print(wordIndex)

在输入期间删除while True循环。无论如何，你在第一次迭代后就破了。在循环中使用时，enumerate()将返回元素的索引以及元素。这样你就忘记了调用index()

如何得到两个答案

5 个答案: