#include <bits/stdc++.h>
using namespace std;




int main(){


int n;
cin >> n;
string s = "";
cin >> s;
string ss = "";
ss += s[0];
int k = 1;
for (int i = 1; i < n; i++){
    if (s[i-1] == ')' && s[i] == '('){
        ss += "*(";
        k += 2;
    }
    if (s[i-1] == '(' && s[i] == ')'){
        ss += "1)";
        k += 2;
    }
    if (s[i-1] == ')' && s[i] == ')'){
        ss += "+1)";
        k += 3;
    }
    if (s[i-1] == '(' && s[i] == '('){
        ss += "(";
        k += 1;
    }
}
int check = 0, r = 0;
vector <int> a;
for (int i = 0; i < k; i++){
    if (check == 1 && ss[i] == '('){
        check = 0;
        if (r != 0){
            a.push_back(r);

        }
        r = 0;
    }
    if (ss[i] == '1'){
        r++;
    }
    if (ss[i] == ')'){
        check = 1;
    }

}
if (r != 0){
    a.push_back(r);
}
int ans = 1;
for (auto to: a){
    ans *= to;
}
cout << ans;
}