Is isogram
Implement a function that determines whether a string is an isogram (no repeated letters, case-insensitive).
Is pangram?
Implement is_pangram(s) to return True if the string contains every letter from 'a' to 'z' at least once, ignoring case and non-alphabetic characters.
Mask email address
Given an email address, return a masked version that hides everything but the first and last character of the local part and the domain.
Is isogram?
Write a function that checks whether a given word is an isogram, ignoring letter case and only considering alphabetic characters.
Validate time format
Check whether a given string is a valid 24-hour time in HH:MM format.
Validate username format
Implement a function that validates a username according to length, allowed characters, and no consecutive underscores.
Minimum Remove Valid Parentheses
Given a string with parentheses and letters, remove the fewest parentheses to make it valid.
Additive number sequence
Check whether a given digit string can be partitioned into a valid additive sequence where each term is the sum of the previous two.
Showing 1–8 of 8 challenges · Strings & Text
Strings & Text — Python coding challenges
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This page lists strings & text challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.
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