p, n= map(int, input().split())
A = list(map(int, input().split()))
s = str(input())
ans = A[0]
for i in range(n-1):
    if s[i] == '+':
        ans += A[i+1]
    elif s[i] == '-':
        ans -= A[i+1]
    elif s[i] == '*':
        ans *= A[i+1]
    else:
        ans *= pow(A[i+1], p-2, p)
    ans %= p
print(ans)