def convert(p, a, q):
    rlist = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    acc = 0
    for d in a:
        r = rlist.find(d)
        acc = acc * p + r
    res = ""
    while acc > 0:
        r = acc % q
        res = rlist[r] + res
        acc = acc // q
    return res

p = int(input())
a = input()
q = int(input())
print(convert(p, a, q))