def count(arr):
    if type(arr) == int:
        return 1
    if len(arr) == 1 and type(arr[0]) != int:
        return 1 + count(arr[0])
    if len(arr) == 1 and type(arr[0]) == int:
        return 1
    res = 1
    for item in arr:
        if type(item) == list:
            res *= count(item) + 1
    return res 
    


def get_res(s):
    #print(s)
    if len(s) == 0:
        return 1
    res = []
    c = 0
    start = 0
    for i in range(len(s)):
        if s[i] == '(':
            c += 1
        else:
            c -= 1
        if c == 0:
            res.append(get_res(s[start + 1: i]))
            start = i + 1
    return res


def main():
    l = int(input())
    s = list(input())
    a = get_res(s)
    #print('get_res:', a)
    c = count(a)
    print(c)
    

if __name__ == '__main__':
    main()