# quiz.py: code to process quizzes

import sys
from typing import *


class Quiz:
    """Track data related to a quiz for an entire section (that is, all students who took the quiz)."""
    def __init__(self, name: str, score_list: List[float]):
        self._name = name.strip()
        self._scores = score_list

    @property
    def name(self) -> str:
        return self._name

    def average(self) -> float:
        """Average of all non-negative scores."""
        nonnegatives = [n for n in self._scores if n > 0]
        if len(nonnegatives) == 0:
            return 0.0
        else:
            return sum(nonnegatives) / len(nonnegatives)


def read_quiz() -> Quiz:
    """Read a quiz from standard input where the first line gives the quiz name and the
    remaining lines give the scores."""
    score_list = []
    name = ''
    for line in sys.stdin:
        if name == '':
            name = line
        else:
            try:
                num = float(line)
            except ValueError:
                break  # done with loop!
            score_list += [num]
    return Quiz(name, score_list)