#!/usr/bin/env python
import itertools

VALS = {}

for i in range(ord('a'), ord('z')+1):
    VALS[chr(i)] = i - ord('a') + 1

for i in range(ord('A'), ord('Z')+1):
    VALS[chr(i)] = i - ord('A') + 27

score = 0

with open('input') as f:
    for elfA,elfB,elfC in itertools.zip_longest(*[f]*3):
        elfA = elfA.rstrip()
        elfB = elfB.rstrip()
        elfC = elfC.rstrip()

        common = set(elfA) & set(elfB) & set(elfC)

        score = score + VALS[common.pop()]

print(score)