First clear solution for Goes Right After by wo.tomasz - python coding challenges

Enable Javascript in your browser and then refresh this page, for a much enhanced experience.

First solution in Clear category for Goes Right After by wo.tomasz

def goes_after(word: str, first: str, second: str) -> bool:
    fidx = word.find(first)
    sidx = word.find(second)
    if fidx+1 >= len(word) or fidx < 0 or sidx < 0:
        return False
    return fidx+1 == sidx


if __name__ == '__main__':
    print("Example:")
    print(goes_after('world', 'w', 'o'))

    # These "asserts" are used for self-checking and not for an auto-testing
    assert goes_after('world', 'w', 'o') == True
    assert goes_after('world', 'w', 'r') == False
    assert goes_after('world', 'l', 'o') == False
    assert goes_after('panorama', 'a', 'n') == True
    assert goes_after('list', 'l', 'o') == False
    assert goes_after('', 'l', 'o') == False
    assert goes_after('list', 'l', 'l') == False
    assert goes_after('world', 'd', 'w') == False
    print("Coding complete? Click 'Check' to earn cool rewards!")

Nov. 20, 2020

Comments:

koborC on Dec. 29, 2020, 2:55 a.m.
1)I think this condition: fidx+1 >= len(word) is not needed, because if the condition met, which mean the appearance of "first" character is word[-1], then sidx always not match with fidx+1. example: <pre class='brush: python'>word = "word" len(word) # = 4 fidx = word.index("d") # = 3 word[fidx+1] # IndexError: string index out of range # so sidx should not match fidx+1 because it is out of range. </pre> 2)sidx < 0 is not needed, because if sidx is negative, then fidx+1 == sidx is always False, because fidx >= -1 and fidx+1 >= 0. sry if you write these conditions for clarity.

Orthomonalus on April 8, 2026, 5:04 p.m.
This is a very logical approach, is a great way to handle basic presence checks

Strings and Integers

0 %

You ClassRoom Demo is Ready With the new tool CheckiO ClassRoom, you will be able to analyze your students' progress, have your own leaderboard, change missions order on the map, and so on.