n = int(input())
s = list(input().rstrip())
mod = 998244353
if s[0] == '(' and s[1] == ')':
    ans = pow(2,n//2,mod)
    print(ans)
else:
    class comb():
        def __init__(self,n,mod):
            self.fact = [0] * (n+1)
            self.fact_inv = [0] * (n+1)
            self.mod = mod
    
            self.fact[1] = 1
            self.fact_inv[1] = pow(1,mod-2,mod)
            self.fact[0] = 1
            self.fact_inv[0] = 1
    
            for i in range(2,n+1):
                self.fact[i] = (self.fact[i-1] * i) % mod
                self.fact_inv[i] = (self.fact_inv[i-1] * pow(i,mod-2,mod)) % mod
        def ncr(self,n,r):
            if n-r < 0:
                return 0
            return (self.fact[n] * self.fact_inv[r] * self.fact_inv[n-r]) % self.mod
        def nhr(self,n,r):
            return self.ncr(n+r-1,r)
    c = comb(500000+10,mod)
    ans = 0
    for i in range(n//2 + 1):
        x = c.ncr(n//2,i)
        ans += x * x
        ans %= mod
    print(ans)