import os

f = open(os.path.dirname(__file__)+"/input.txt", "r")

tot = 0
tot2 = 0

priorities = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"


commons = ''

rucksacks = f.read().splitlines()

for data in rucksacks:
    left = data[:len(data)//2]
    right = data[len(data)//2:]
    print(str(left) + " " + str(right))

    common = ''.join(set(left).intersection(right))

    tot = tot + priorities.rfind(common)+1

print(tot)