p, n = map(int, input().split())
a = list(map(int, input().split()))
s = input().strip()

current = a[0] % p

for i in range(1, n):
    op = s[i-1]
    num = a[i] % p
    if op == '+':
        current = (current + num) % p
    elif op == '-':
        current = (current - num) % p
    elif op == '*':
        current = (current * num) % p
    elif op == '/':
        inv = pow(num, p-2, p)
        current = (current * inv) % p

print(current)