from typing import List
import math


def checkio(data: List[int]) -> [int, float]:
    data.sort()
    data_len = len(data)
    if data_len % 2 == 0:
        if data_len != 2:
            cut = int(data_len / 2 - 1)
            data = data[cut:-cut]
        return sum(data) / len(data)
    middle = math.floor(data_len / 2)
    return data[middle]


# These "asserts" using only for self-checking and not necessary for auto-testing
if __name__ == '__main__':
    print("Example:")
    print(checkio([1, 2, 3, 4, 5]))

    assert checkio([1, 2, 3, 4, 5]) == 3, "Sorted list"
    assert checkio([3, 1, 2, 5, 3]) == 3, "Not sorted list"
    assert checkio([1, 300, 2, 200, 1]) == 2, "It's not an average"
    assert checkio([3, 6, 20, 99, 10, 15]) == 12.5, "Even length"
    print("Start the long test")
    assert checkio(list(range(1000000))) == 499999.5, "Long."
    assert checkio([10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0]) == 5, "5."
    assert checkio([999999, 1]) == 5, "5."
    print("Coding complete? Click 'Check' to earn cool rewards!")