file = open('input.txt','r')

input = []
aset = []

for l in file:
    if l == '\n':
        input.append(aset)
        aset = []
    else:
        aset.append(l.replace('\n',''))
input.append(aset)

sum = 0
for i in input:
    res = []
    print(i)
    for c in i[0]:
        count = 0
        for s in i:
            if c in s:
                count += 1
        if count == len(i):
            res.append(c)
    print(res)
    print(str(len(res)))
    sum += len(res)
    print(str(sum))
    print('-' * 50)
print(str(sum))