import sys

def solve():
    input_data = sys.stdin.read().split()
    if len(input_data) < 2:
        return
    
    n = int(input_data[0])
    s = input_data[1]
    MOD = 998244353

    ans = 1
    i = 0
    while i < n:
        if s[i] == '0':
            zeros = 0
            while i < n and s[i] == '0':
                zeros += 1
                i += 1
            
            if i < n and s[i] == '1':
                ones = 0
                while i < n and s[i] == '1':
                    ones += 1
                    i += 1
                
                ans = (ans * (zeros + ones)) % MOD
        else:
            i += 1
            
    print(ans)

if __name__ == "__main__":
    solve()