import os
import sys

dir = os.path.dirname(os.path.abspath(__file__))

with open(os.path.join(dir, './input.txt'), 'r') as input_file:

    lines = input_file.readlines()

    line = lines[0].strip()
    crabsString = line.split(',')
    crabs = [int(numeric_string) for numeric_string in crabsString]

    maxDistance = max(crabs)
    minDistance = min(crabs)

    smallestFuel = 9999999999999999999999
    for i in range(minDistance, maxDistance+1):
        currentfuel = 0
        for crab in crabs:
            steps = abs(crab-i)
            a_sum = steps*((steps+1)/2)
            currentfuel = currentfuel + a_sum
        
        smallestFuel = min(smallestFuel, currentfuel)

    print(smallestFuel)