P,N = map(int,input().split())
A = list(map(int,input().split()))
S = input()

ans = A[0]
for i in range(N-1):
    if S[i] == '+':
        ans += A[i+1]
        ans %= P
    elif S[i] == '*':
        ans = (ans * A[i+1]) % P
    elif S[i] == '-':
        ans = (ans - A[i+1]) % P
    else:
        inv = pow(A[i+1],P-2,P)
        ans = (ans * inv) % P
print(ans)