def main() -> None:
    with open("data.txt", 'r') as data:
        nums = [int(v) for v in data]
        # print(sum(nums))
        n = len(nums)
        x_m = sum(nums) / n
        print(f"x_m = {x_m}")
        s_shifted = 0

        for v in nums: s_shifted += (x_m - v) ** 2

        s_shifted = s_shifted / n

        s_unshifted = s_shifted * n / (n - 1)

        print(f"смещенная дисперсия = {s_shifted}")
        print(f"несмещенная дисперсия = {s_unshifted}")

if __name__ == "__main__":
    main()