import sys

a = ''
b = ''
c = ''

def check(a, b):
    if a == b:
        return True
    if len(a) != len(b):
        return False
    d = 0
    for i in range(len(a)):
        if a[i] != b[i]:
            d += 1
            if d > 1:
                return False
    return d == 1

def cnt(a, b, c):
    d = 0
    if check(a, b):
        d += 1
    if check(b, c):
        d += 1
    if check(a, c):
        d += 1
    return d

if __name__ == '__main__':
    sys.stdin = open('tuongduong.inp', 'r')
    sys.stdout = open('tuongduong.out', 'w')
    a, b, c = input().split()
    print(cnt(a, b, c))