Python: Matches a string that has an a followed by zero or more b's

Last update on April 23 2025 12:59:55 (UTC/GMT +8 hours)

2. a Followed by 0+ b's

Write a Python program that matches a string that has an a followed by zero or more b's.

Sample Solution:

Python Code:

import re
def text_match(text):
        patterns = '^a(b*)$'
        if re.search(patterns,  text):
                return 'Found a match!'
        else:
                return('Not matched!')
print(text_match("ac"))
print(text_match("abc"))
print(text_match("a"))
print(text_match("ab"))
print(text_match("abb"))

Sample Output:

Not matched!
Not matched!
Found a match!
Found a match!
Found a match!

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to match strings that start with 'a' and are optionally followed by any number of 'b's, then print all matches.
• Write a Python program that checks if a string begins with 'a' and is optionally followed by 'b's, using regex.
• Write a Python program to validate user input where the pattern is an 'a' optionally followed by repeated 'b's, and output a confirmation message.
• Write a Python program to find and print all substrings in a text that match the pattern 'a' followed by zero or more 'b's.

Go to:

• Python Regular Expression Exercises Home ↩
• Python Exercises Home ↩

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Next: Write a Python program that matches a string that has an a followed by one or more b's.

Python Code Editor:

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