#include<bits/stdc++.h>
using namespace std;
const int mod = 1000000007;
int n, m, ans = 0;
string s;
int dfs2(int x, int c, string s2) {
    if(x > c) {
        int kh = 0, f = 1;
        for(int i = 0; i < s2.length(); i ++) {
            if(s2[i] == ')' && kh == 0) {
                f = 0;
                break;
            }
            if(s2[i] == ')') {
                kh --;
            }
            if(s2[i] == '(') {
                kh ++;
            }
        }
        if(kh == 0 && f == 1) {
            ans ++;
        }
        return 0;
    }
    dfs2(x + 1, c, s2 + ")");
    dfs2(x + 1, c, s2 + "(");
    return 0;
}
int dfs(int x, int c, string s1) {
    if(x > c) {
        return 0;
    }
    dfs2(1, c - x, s1 + s);
    dfs(x + 1, c, s1 + "(");
    dfs(x + 1, c, s1 + ")");
    return 0;
}
int main() {
    freopen("tribrackets.in", "r", stdin);
    freopen("tribrackets.out", "w", stdout);
    cin >> n >> m >> s;
    dfs(0, n - m, "");
    if(n == m) {
        cout << 1 << endl;
        return 0;
    }
    cout << ans << endl;
    return 0;
}