from string import ascii_letters as lett

value = {}
score = 0

for i in range(len(lett)):
    value[lett[i]] = i+1

f = open('input3.txt', 'r')
inp = f.read().splitlines(keepends=False)


for i in range(len(inp)):
    b = int(len(inp[i])/2)
    fir = inp[i][b:]
    sec = inp[i][:b]
    for x in range(len(fir)):
        if fir[x] in sec:
            charr = fir[x]
            break
    score = score + value[charr]
print(score)