values = []
with open('data', 'r') as fp:
    values = fp.readline().strip().split(',')
for i in range(0, len(values)):
    values[i] = int(values[i])
values.sort()

index = int(len(values) / 2)
total = 0
for i in range(0, len(values)):
    if(i != index):
        total += abs(values[i] - values[index])
print(total)