from math import ceil, floor


def kys(l):
    s_n = l[1:-1].split(', ')
    if '/' in s_n[0]:
        s_n[0] = calculate(s_n[0])
    else:
        s_n[0] = int(s_n[0])
    if '/' in s_n[1]:
        s_n[1] = calculate(s_n[1])
    else:
        s_n[1] = int(s_n[1])
    return s_n


def calculate(s_val):
    s_splitted = s_val.split('/')
    return int(s_splitted[0])/int(s_splitted[1])


s = input()
fb = s[0]
lb = s[-1]

if fb == '[' and lb == ']':
    s_new = kys(s)
    print(floor(s_new[1]) - ceil(s_new[0]) + 1)
elif fb == '(' and lb == ')':
    s_new = kys(s)
    if round(s_new[0]) == s_new[0] or round(s_new[1]) == s_new[1]:
        print(ceil(s_new[1] - s_new[0]) - 1)
    else:
        print(floor(s_new[1] - s_new[0]))
else:
    s_new = kys(s)
    if (round(s_new[0]) == s_new[0] and fb == '[') or (round(s_new[1]) == s_new[1] and lb == ']'):
        print(ceil(s_new[1] - s_new[0]))
    else:
        print(floor(s_new[1] - s_new[0]))