Python Program that Extract words starting with Vowel From A list
Given a list with string elements, the following program extracts those elements which start with vowels(a, e, i, o, u).
Input : test_list = [“all”, “love”, “get”, “educated”, “by”, “gfg”]
Output : [‘all’, ‘educated’]
Explanation : a, e are vowels, hence words extracted.
Input : test_list = [“all”, “love”, “get”, “educated”, “by”, “agfg”]
Output : [‘all’, ‘educated’, ‘agfg’]
Explanation : a, e, a are vowels, hence words extracted.
Method 1 : Using startswith() and loop
In this, we check for each word and check if it starts with a vowel using startswith() on the first alphabet of every word. The iteration part is done using the loop.
Python3
# initializing listtest_list = ["all", "love", "and", "get", "educated", "by", "gfg"]# printing original listprint("The original list is : " + str(test_list))res = []vow = "aeiou"for sub in test_list: flag = False # checking for begin char for ele in vow: if sub.startswith(ele): flag = True break if flag: res.append(sub)# printing result print("The extracted words : " + str(res)) |
The original list is : ['all', 'love', 'and', 'get', 'educated', 'by', 'gfg'] The extracted words : ['all', 'and', 'educated']
Time Complexity: O(N)
Auxiliary Space: O(N)
Method 2 : Using any(), startswith() and loop
In this, we check for vowels using any(), and rest all the functionality is similar to the above method.
Python3
# initializing listtest_list = ["all", "love", "and", "get", "educated", "by", "gfg"]# printing original listprint("The original list is : " + str(test_list))res = []vow = "aeiou"for sub in test_list: # check for vowel beginning flag = any(sub.startswith(ele) for ele in vow) if flag: res.append(sub)# printing result print("The extracted words : " + str(res)) |
The original list is : ['all', 'love', 'and', 'get', 'educated', 'by', 'gfg'] The extracted words : ['all', 'and', 'educated']
Time Complexity: O(n2)
Auxiliary Space: O(n)
Method 3 : Using find() method
Python3
#Starting with vowels# initializing listtest_list = ["all", "love", "and", "get", "educated", "by", "gfg"]# printing original listprint("The original list is : " + str(test_list))def vowelstart(s): if(s[0]=="a" or s[0]=="e" or s[0]=="i" or s[0]=="o" or s[0]=="u"): return True return Falseres = []for sub in test_list: if(vowelstart(sub)): res.append(sub)# printing resultprint("The extracted words : " + str(res)) |
The original list is : ['all', 'love', 'and', 'get', 'educated', 'by', 'gfg'] The extracted words : ['all', 'and', 'educated']
Time Complexity: O(N)
Auxiliary Space: O(N)
Method 4 : Using for loop
Python3
# Python Program that Extract words starting# with Vowel From A list initializing listtest_list = ["all", "love", "and", "get", "educated", "by", "gfg"]# Printing original listprint("The original list is : " + str(test_list))res = []vow = "aeiou"for i in test_list: if i[0] in vow: res.append(i) # Printing resultprint("The extracted words : " + str(res)) |
The original list is : ['all', 'love', 'and', 'get', 'educated', 'by', 'gfg'] The extracted words : ['all', 'and', 'educated']
Time Complexity: O(N)
Auxiliary Space: O(N)
Method #5: Using filter(),list(),lambda functions and dictionary
Python3
# Starting with vowels# initializing listtest_list = ["all", "love", "and", "get", "educated", "by", "gfg"]vowels = { "a": 0, "e": 0, "i": 0, "o": 0, "u": 0}# printing original listprint("The original list is : " + str(test_list))res = list(filter(lambda x: x[0] in vowels.keys(), test_list))# printing resultprint("The extracted words : " + str(res)) |
The original list is : ['all', 'love', 'and', 'get', 'educated', 'by', 'gfg'] The extracted words : ['all', 'and', 'educated']
Time Complexity: O(N)
Auxiliary Space: O(N)
Method #6: Using operator.countOf() method
Python3
# Python Program that Extract words starting# with Vowel From A list initializing listimport operator as optest_list = ["all", "love", "and", "get", "educated", "by", "gfg"]# Printing original listprint("The original list is : " + str(test_list))res = []vow = "aeiou"for i in test_list: if op.countOf(vow, i[0]) > 0: res.append(i)# Printing resultprint("The extracted words : " + str(res)) |
The original list is : ['all', 'love', 'and', 'get', 'educated', 'by', 'gfg'] The extracted words : ['all', 'and', 'educated']
Time Complexity: O(N)
Auxiliary Space : O(N)
Method#7: Using regular expression
Python3
import re# initializing listtest_list = ["all", "love", "and", "get", "educated", "by", "gfg"]# printing original listprint("The original list is : " + str(test_list))vow = "aeiou"res = [x for x in test_list if re.match(f"^[{vow}]", x)]# printing result print("The extracted words : " + str(res))#This code is contributed by Vinay Pinjala. |
The original list is : ['all', 'love', 'and', 'get', 'educated', 'by', 'gfg'] The extracted words : ['all', 'and', 'educated']
Time Complexity: O(N)
Auxiliary Space : O(N)
Method#8: Using list comprehension and ‘in’
Here’s another approach using a list comprehension and checking if the first character is a vowel using in operator:
Python3
test_list = ["all", "love", "and", "get", "educated", "by", "gfg"]# Printing original listprint("The original list is : " + str(test_list))res = [word for word in test_list if word[0] in "aeiou"]# Printing resultprint("The extracted words : " + str(res)) |
The original list is : ['all', 'love', 'and', 'get', 'educated', 'by', 'gfg'] The extracted words : ['all', 'and', 'educated']
Time Complexity: O(N)
Auxiliary Space: O(N)
