# retoor <retoor@molodetz.nl>

from typing import Union


def add(left: int, right: int) -> int:
    return left + right


def subtract(left: int, right: int) -> int:
    return left - right


def clamp(value: int, low: int, high: int) -> int:
    if low > high:
        raise ValueError
    if value < low:
        return low
    if value > high:
        return high
    return value


def clamp_to_byte(value: int) -> int:
    return max(0, min(255, value))


def percentage(value: Union[int, float], total: Union[int, float]) -> float:
    if total == 0:
        raise ValueError
    return (value / total) * 100