import shared
from pprint import pp
from scipy import stats
import numpy as np


class Whale:
    def __init__(self, name):
        self.load(name)
        self.set_target()

    def load(self, name):
        with open(name, "r") as f:
            self.positions = list(map(int, f.read().split(",")))

    def set_target(self):
        data = np.array(self.positions)
        self.target = round(np.mean(data))

    def calculate(self, target=None):
        return int(sum([self.sigma(abs(target - pos)) for pos in self.positions]))

    def sigma(self, value):
        return value * (value + 1) / 2


def main():
    w = Whale(shared.get_fname(7))
    if w.target in w.positions:
        target = w.target
    else:
        target = w.target - 1
    pp(w.calculate(target))


if __name__ == "__main__":
    main()