#include <iostream>
#include <set>
#include <stack>

using namespace std;

long int N;

char getNext() {
    if (--N < 0)
        return '_';
    char res;
    cin >> res;
    return res;
}

long int compute2(long int depth) {
    char c = getNext();
    if (c == ')')
        return depth * compute2(depth);
    else if (c == '(')
        return compute2(depth+1);

    return -1;
}

long int compute(char current) {
    long int sum = 0;
    long int opened = 0;

    if (current == '(')
        opened++;

    for (char next = getNext(); next != '_'; next = getNext()) {
        if (next == '(')
            opened++;
        else if (next == ')')
            opened--;

        if (current == '(' && next == ')')
            sum++;
        else if (current == ')' && next == ')')
            sum++;
        else if (current == ')' && next == '(') {
            sum = sum * compute(next);
        }

        if (opened == 0 && next == ')'  && cin.peek() != '(')
            return sum;

        current = next;
    }

    return sum;
}


int main() {
    cin >> N;

    cout << compute(getNext()) << endl;
    return 0;

    long int sum = 1;
    for (char next = getNext(); next != '_'; next = getNext()) {
        if (next == '(') {
            sum = sum * compute2(0);
        }
    }

    cout << sum << endl;
    return 0;
}


//long int main() {
//    long int nmbOfChars;
//    cin >> nmbOfChars;
//
//    long int sum = 0;
//    char lastChar = '_';
//    for (; nmbOfChars > 0; --nmbOfChars) {
//        char currentChar;
//        cin >> currentChar;
//
//        if (lastChar == '(' && currentChar == ')') {
//            sum++;
//        }
//        if (lastChar == ')' && currentChar == ')') {
//            sum++;
//        }
//        lastChar = currentChar;
//    }
//    cout << sum << endl;
//
//    return 0;
//}