with open("input3.txt") as f:
    a = dict(zip(map(chr,(list(range(97,123))+list(range(65,91)))),range(1,53)))
    s = 0
    h = []
    for line in f.readlines():
        h.append(set(line.strip()))
        if len(h) < 3:
            continue
        s += a[(h[0]&h[1]&h[2]).pop()]
        h = []
    print(s)