using namespace std;
const int MOD = 10007;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int L; string s;
    cin >> L;
    getline(cin, s);      // 吃掉换行
    getline(cin, s);      // L=0 时第二行为空串，必须用 getline

    vector<pair<int,int>> ops;   // 操作数栈 (ways0, ways1)
    vector<char> stk;            // 运算符栈（含 '('）

    auto apply = [&](char op) {
        auto b = ops.back(); ops.pop_back();
        auto a = ops.back(); ops.pop_back();
        int w0, w1;
        if (op == '*') {         // ×：结果为 1 当且仅当两边都为 1
            w0 = (a.first*b.first + a.first*b.second + a.second*b.first) % MOD;
            w1 = (a.second*b.second) % MOD;
        } else {                 // +：结果为 0 当且仅当两边都为 0
            w0 = (a.first*b.first) % MOD;
            w1 = (a.first*b.second + a.second*b.first + a.second*b.second) % MOD;
        }
        ops.push_back({w0, w1});
    };

    bool expectOperand = true;
    for (char c : s) {
        if (c == '(') { stk.push_back(c); continue; }
        if (expectOperand) { ops.push_back({1,1}); expectOperand = false; }
        if (c == ')') {
            while (!stk.empty() && stk.back() != '(') { apply(stk.back()); stk.pop_back(); }
            if (!stk.empty()) stk.pop_back();          // 弹 '('
            expectOperand = false;
        } else if (c == '*') {
            stk.push_back('*');
            expectOperand = true;
        } else {                                       // '+'
            while (!stk.empty() && stk.back() == '*') { apply(stk.back()); stk.pop_back(); }
            stk.push_back('+');
            expectOperand = true;
        }
    }
    if (expectOperand) ops.push_back({1,1});           // 末尾变量
    while (!stk.empty()) { apply(stk.back()); stk.pop_back(); }

    cout << ops.back().first % MOD << '\n';
    return 0;
}

#include <iostream>
#include <stack>
#include <string>
using namespace std;
const int MOD = 10007;

struct Node {
    int dp0, dp1;
    Node(int a=0,int b=0):dp0(a),dp1(b){}
};

int pri(char c){
    if(c == '(') return 0;
    if(c == '+') return 1;
    if(c == '*') return 2;
    return -1;
}

Node calc(Node x, Node y, char op){
    Node res;
    if(op == '*'){
        res.dp0 = (1LL*x.dp0*(y.dp0+y.dp1)%MOD + 1LL*x.dp1*y.dp0%MOD )% MOD;
        res.dp1 = 1LL*x.dp1 * y.dp1 % MOD;
    }else{ // '+'
        res.dp0 = 1LL*x.dp0 * y.dp0 % MOD;
        res.dp1 = (1LL*x.dp0*y.dp1 + 1LL*x.dp1*y.dp0 + 1LL*x.dp1*y.dp1) % MOD;
    }
    return res;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int L;
    string s;
    cin >> L >> s;
    stack<Node> st;
    stack<char> op;
    st.emplace(1,1); //第一个变量
    for(char ch : s){
        if(ch == '('){
            op.push(ch);
            st.emplace(1,1);
        }else if(ch == ')'){
            while(op.top() != '('){
                char o = op.top(); op.pop();
                Node b = st.top(); st.pop();
                Node a = st.top(); st.pop();
                st.push(calc(a,b,o));
            }
            op.pop(); // pop '('
        }else{ // '+' or '*'
            while(!op.empty() && pri(op.top()) >= pri(ch)){
                char o = op.top(); op.pop();
                Node b = st.top(); st.pop();
                Node a = st.top(); st.pop();
                st.push(calc(a,b,o));
            }
            op.push(ch);
            st.emplace(1,1); //新变量
        }
    }
    while(!op.empty()){
        char o = op.top(); op.pop();
        Node b = st.top(); st.pop();
        Node a = st.top(); st.pop();
        st.push(calc(a,b,o));
    }
    cout << st.top().dp0 << endl;
    return 0;
}
```

```