TheAlgorithms/Python · error · ValueError

solution() only accepts values from 0 to 100

Error message

solution() only accepts values from 0 to 100

What it means

Raised by solution() in project_euler/problem_112/sol1.py when percent is not strictly between 0 and 100 (check: not 0 < percent < 100). The function searches for the least number whose bouncy proportion reaches percent, which is only well-defined inside the open interval; 0, 100, and out-of-range values are rejected. Floats are accepted here, unlike the int-only helpers.

Source

Thrown at project_euler/problem_112/sol1.py:75

    Returns the least number for which the proportion of bouncy numbers is
    exactly 'percent'
    >>> solution(50)
    538
    >>> solution(90)
    21780
    >>> solution(80)
    4770
    >>> solution(105)
    Traceback (most recent call last):
        ...
    ValueError: solution() only accepts values from 0 to 100
    >>> solution(100.011)
    Traceback (most recent call last):
        ...
    ValueError: solution() only accepts values from 0 to 100
    """
    if not 0 < percent < 100:
        raise ValueError("solution() only accepts values from 0 to 100")
    bouncy_num = 0
    num = 1

    while True:
        if check_bouncy(num):
            bouncy_num += 1
        if (bouncy_num / num) * 100 >= percent:
            return num
        num += 1


if __name__ == "__main__":
    from doctest import testmod

    testmod()
    print(f"{solution(99)}")

View on GitHub (pinned to f5988cc097)

Solutions

1. Pass a value strictly inside (0, 100), e.g. solution(99) for the canonical problem.
2. If your input is a fraction (0-1), multiply by 100 first: solution(frac * 100).
3. Validate range in your UI/config layer: if not 0 < pct < 100: reject.
4. For '100% bouncy' style requests, cap to 99.999 or handle as a special case outside this API.

Example fix

# before
pct = 100  # user asked for 'all bouncy'
solution(pct)  # ValueError

# after
pct = min(pct, 99.999)
solution(pct)

if not 0 < percent < 100:
    raise ValueError(f"percent must be in (0, 100) exclusive, got {percent}")
solution(percent)

def is_valid_percent(p) -> bool:
    return isinstance(p, (int, float)) and 0 < p < 100

try:
    num = solution(percent)
except ValueError as e:
    if "0 to 100" in str(e):
        num = solution(min(max(percent, 0.001), 99.999))
    else:
        raise

When it happens

Trigger: solution(105), solution(100.011), solution(0), solution(100), solution(-5). Note the endpoints themselves are rejected: solution(100) raises even though 100 looks reasonable (the proportion never provably reaches exactly 100% in the incremental search).

Common situations: User-supplied percentage fields without range validation; passing 100 expecting 'all bouncy'; unit tests probing boundary values; sign errors or percent-vs-fraction confusion (passing 0.99 instead of 99).

Related errors

• Parameter nth must be greater than or equal to one.
• n must be >= 0
• Hand should contain only 5 cards: {hand!r}
• gon_side must be in the range [3, 5]
• a gon ring should have a length that is a multiple of 3

AI-assisted analysis of TheAlgorithms/Python@f5988cc097 (2026-08-14). Data as JSON: /api/errors/2ea73eb908542521. Report an issue: GitHub.