Question

我是python的新手-

我必须构建一个名为'first__vowel'的函数。接受字符串列表作为输入并返回以小写元音("a","e","i","o", or "u")开头的第一个字符串。如果没有以元音开头的字符串，请返回空字符串("")。

您能帮助构建此功能吗？

谢谢

Answer 1

检查：

vowels = ["a", "e", "i", "o", "u"]

def first_vowel(ss):
    for s in ss:
        if s and s[0] in vowels:
            return s
    return ""

测试：

first_vowel(["Drere", "fdff", "", "aBD", "eDFF"])
'aBD'

Answer 2

您需要：

def first_vowel(lst):
    # iterate over list using for loop
    for i in lst:
        # check if first letter is vowel
        if i and i[0] in ['a','e','i','o','u']:
            return i 
    return ""

k = ['sad','dad','mad','asd','eas']
print(first_vowel(k))

或者您也可以使用regex

import re

def first_vow(lst):
    pat = re.compile(r'^[aeiou][a-zA-Z]*')
    for i in lst:
        match = re.match(pat, lst)
        if match:
            return i
    return ""

k = ['sad','Aad','mad','','asd','eas']
first_vow(k)

Answer 3

您也可以随时使用str.startswith()功能：

def first_vowel(lst):
    for elem in lst:
        if elem.startswith(('a','e','i','o','u')):
            return elem
    return ''
k = ['', 'b','sad','dad','mad','asd','eas']
print(first_vowel(k))

Answer 4

l1 = ['hi', 'there', 'its', 'an' , 'answer', '']

def first_vowel(var):
    for i in var:
        if i.startswith(('a', 'e', 'i', 'o', 'u')): return i


first_vowel(l1) # output-> 'its'

在LIST Python中找到以元音开头的第一个字符串

4 个答案: