from functools import reduce; from math import gcd; lcm = lambda a, b: abs(a*b) // gcd(a, b)
def merge(a, b, x, y):
    while b != y: b += a * (max(-1, y-b-1) // a + 1); y += x * (max(-1, b-y-1) // x + 1); return lcm(a, x), b
print(reduce(lambda fn, fm: merge(*fn, *fm), ((int(x), -idx) for idx, x in enumerate([x.strip() for x in open("input.txt")][1].split(',')) if x != 'x'), (1, 0))[1])