MOD = 998244353

n = int(input())
S = input()
dp = {0:1}
for s in S:
    ndp = {}
    for rb, v in dp.items():
        r = rb // n
        b = rb - r * n
        if s == "(":
            x = rb + n
            ndp[x] = ndp.get(x, 0) + v
            ndp[x] %= MOD
            x = rb + 1
            ndp[x] = ndp.get(x, 0) + v
            ndp[x] %= MOD
        else:
            if r >= 1:
                x = rb - n
                ndp[x] = ndp.get(x, 0) + v
                ndp[x] %= MOD
            if b >= 1:
                x = rb - 1
                ndp[x] = ndp.get(x, 0) + v
                ndp[x] %= MOD
    dp = ndp
    
print(ndp.get(0, 0))