dic = 'abcdefghijklmnopqrqtuvwxyz,.'
a = input()
s = 0
a = a.replace('.', ',')
for i in range(a.count(',')):
    for el in a[:a.find(',')]:
        if a.find(el) == a.find(',') - 1 and el in dic and a.find(el) < len(a) - 1 and dic.find(el) <= dic.find(a[a.find(el) + 1]):
            s = s + 1
        elif a.find(el) != a.find(',') - 1 and el in dic and a.find(el) < len(a) - 1 and dic.find(el) <= dic.find(a[a.find(el) + 1]):
            pass
        else:
            break
    a = a.replace(a[:a.find(',') + 1], '')
print(s)