n = int(input())
s = input().strip()

dp = [0] * (n + 1)
dp[0] = 1

for i in range(1, n + 1):
    if s[i - 1] != '0':
        dp[i] += dp[i - 1]
    
    if i > 1:
        two_digit = int(s[i - 2:i])
        if 10 <= two_digit <= 26:
            dp[i] += dp[i - 2]

print(dp[n])