如何在列表中找到特定项目的索引？

Question

我想在输出中打印带有索引号的项目，但我做不到。我的脚本是这样工作的：

1.Takes 来自用户的字符串并删除句点和逗号。 2. 将字符串拆分为名为 reshte. 的列表。 3. 从索引 0 处的列表中删除第一项。 4. 扫描第一个字符为大写的列表，然后在输出中显示。

输入：

The Persian League is the largest sport event dedicated to the deprived areas of Iran. The Persian League promotes peace and friendship. This video was captured by one of our heroes who wishes peace.

我的代码：

bs = [',','.']
reshte = input()
for s in bs:
    if s in reshte:
        reshte = reshte.replace(s,'')

reshte = reshte.split()
b = reshte[0]
css = [reshte.remove(b) for k in reshte if b in reshte]


for f in reshte:
    if f[0] == f[0].upper():
       print(f)

输出：

Persian
League
Iran
Persian
League

预期输出：

2:Persian
3:League
15:Iran
17:Persian
18:League

Answer 1

使用枚举和打印的 sep 选项解决这个问题。只需更改最后一个for循环即可。

for i, f in enumerate(reshte):
    if f[0] == f[0].upper():
       print(i, f, sep=":")

Answer 2

@Patrick 确实给了你一个答案但是你说那是错误的，我假设索引的结果应该是索引 before 删除第一个元素列出（第 3 步）并将索引加 1，因为结果似乎是我们通常计算的索引，而不是 Python（或大多数编程语言，请参阅下面的指南）中计算的索引。

我还看到结果中没有单词 'This' 所以我假设您希望 ALSO 跳过所有以大写字母开头的单词与列表的第一个元素相同，所以单词 'The'.

1。使用列表作为结果

test_string = """The Persian League is the largest sport event dedicated, \
to the deprived, areas of Iran. The Persian League promotes, peace and friendship.  
This video was captured by one of our heroes, who wishes peace.
"""

bs = [',', '.']
result_2 = []
# ========== < REMOVE COMMAS AND DOTS > ========= #
for punct in bs:
    if punct in test_string:
        test_string = test_string.replace(punct, '')


# ========== < STORE FIRST ELEMENT AT INDEX 0 > ========= #
reshte = test_string.split()
first_element = reshte[0]


# ========== < COUNTS ELEMENTS IN LIST > ========= #
results = []
for idx, f in enumerate(reshte):
    if first_element[0] == f[0]: # NOTE: we don't remove the first element but only skipping it all in once
        continue
    if f[0].isupper():
        results.append((idx, f))

for idx, value in results:
    print(f'{idx+1}:{value}')

# 2:Persian
# 3:League
# 15:Iran
# 17:Persian
# 18:League

2。使用字典

results = dict()
for idx, f in enumerate(reshte):
    if first_element[0] == f[0]: # NOTE: we don't remove the first element
        continue
    if f[0].isupper():
        results[idx] = f

for key, value in results.items():
    print(f'{key+1}:{value}')
    
# 2:Persian
# 3:League
# 15:Iran
# 17:Persian
# 18:League

print(results)

# {1: 'Persian', 2: 'League', 14: 'Iran', 16: 'Persian', 17: 'League'}

3。计数列表的重复项

# ========== < FIND UNIQUE ELEMENT IN LIST > ========= #
unique_string = {string for string in reshte if string[0].isupper()}
results = []
# ========== < COUNT ELEMENTS  > ========= #
for element in unique_string:
    if first_element[0] == element[0]:
        continue
    element_count = reshte.count(element)
    results.append((element_count, element))

for idx, value in results:
    print(f'{idx}:{value}')
# 1: Iran
# 2: League
# 2: Persian

4。使用计数器

from collections import Counter

counted = Counter(reshte)

for element, count in counted.items():
    if element[0] == first_element[0]:
        continue
    elif element[0].isupper():
        print(f'{count}:{element}')
        
# 2:Persian
# 2:League
# 1:Iran

指南和文档

Stack Overflow 相关问题

Checking if first letter of string is in uppercase
understanding-slice-notation
how-to-access-list-elements
how-can-i-count-the-occurrences-of-a-list-item

如何在列表中找到特定项目的索引？

How find indices of specific items in a list?

python

list

algorithm

indexing

enumerate