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:
        if b < y: b += a * ((y-b-1) // a + 1)
        else: y += x * ((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])