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#include <iostream>
#include <string>
#include <queue>
#include <cstdlib>
#include <limits>
#include <algorithm>
#include <iterator>

const int MAX_N = 1000009;
const int MODULUS = 1000000007;


struct clause {
    int start;
    int end;
    std::deque<bool> val;
    clause() : start(0), end(0) {}
    bool operator==(const clause& other) const {
        return start == other.start && val == other.val;
    }
    void add(int num, bool v) {
        if (start == 0) {
            start = num;
            end = num+1;
            val.push_back(v);
        }
        while (start > num) {
            val.push_front(false);
            --start;
        }
        while (num >= end) {
            val.push_back(false);
            ++end;
        }
        val[num-start] = v;
    }
    int size() const {
        return end - start;
    }
};

int n;
std::vector<clause> clauses;

std::pair<long long, long long> exgcd(long long a, long long b) {
    long long p = 1, q = 0;
    long long r = 0, s = 1;
    while (b != 0) {
        long long c = a % b;
        long long quot = a/b;
        a = b;
        b = c;
        long long r_tmp = r;
        long long s_tmp = s;
        r = p - quot * r;
        s = q - quot * s;
        p = r_tmp;
        q = s_tmp;
    }
    return std::make_pair(p, q);
}

long long invert(long long a) {
    return exgcd(a, MODULUS).first;
}

struct mod_num {
    long long val;
    mod_num() : val(0) {}
    mod_num(long long v) {
        val = v;
        val %= MODULUS;
        val += MODULUS;
        val %= MODULUS;
    }
    mod_num& operator+=(const mod_num& o) {
        val += o.val;
        val %= MODULUS;
    }
    mod_num& operator-=(const mod_num& o) {
        val += MODULUS;
        val -= o.val;
        val %= MODULUS;
        return *this;
    }
    mod_num& operator*=(const mod_num& o) {
        val *= o.val;
        val %= MODULUS;
        return *this;
    }
    mod_num& operator/=(const mod_num& o) {
        return (*this) *= invert(o.val);
    }
    mod_num operator+(const mod_num& o) {
        mod_num rv(*this);
        rv += o;
        return rv;
    }
    mod_num operator-(const mod_num& o) {
        mod_num rv(*this);
        rv -= o;
        return rv;
    }
    mod_num operator*(const mod_num& o) {
        mod_num rv(*this);
        rv *= o;
        return rv;
    }
    mod_num operator/(const mod_num& o) {
        mod_num rv(*this);
        rv /= o;
        return rv;
    }
    friend std::ostream& operator<<(std::ostream& os, const mod_num& n) {
        return os << n.val;
    }
};

mod_num modpow(mod_num b, int n) {
    mod_num r = 1;
    while (n) {
        if (n&1) {
            r *= b;
        }
        b *= b;
        n >>= 1;
    }
    return r;
}

std::ostream& operator<<(std::ostream& os, const clause& c) {
    if (c.val.empty()) {
        return os << "false";
    }
    os << "(";
    if (!c.val[0]) {
        os << '~';
    }
    os << "x" << c.start;
    for (int i = 1; i < c.val.size(); ++i) {
        os << " v ";
        if (!c.val[i]) {
            os << '~';
        }
        os << "x" << c.start+i;
    }
    os << ")";
    return os;
}

class parser {
    int pos;
    const std::string& input;
    
    int skipTo(char c) {
        while (input[pos] != c) ++pos;
    }

    void skipAfter(char c) {
        skipTo(c);
        ++pos;
    }

    clause parseClause() {
        clause rv;
        for (;;) {
            bool val = true;
            for (; input[pos] != 'x'; ++pos) {
                if (input[pos] == ')') {
                    ++pos;
                    return rv;
                } else if (input[pos] == '~') {
                    val = false;
                }
            }
            ++pos;
            int num = atoi(input.c_str()+pos);
            rv.add(num, val);
        }
    }
public:
    parser(const std::string& input) : pos(0), input(input) {}
    
    void parse() {
        clauses.push_back(clause());
        while (pos < input.size()) {
            skipTo('(');
            clauses.emplace_back(parseClause());
        }
    }
};

bool check_overlap(const clause& a, const clause& b) {
    if (a.start > b.start)
        return check_overlap(b, a);
    int diff = b.start-a.start;
    int e = std::min(b.size(), a.size()-diff);
    for (int i = 0; i < e; ++i) {
        if (a.val[i+diff] != b.val[i])
            return false;
    }
    return true;
}

bool check_in(const clause& a, const clause& b) {
    if (a.size() > b.size())
        return check_in(b, a);
    int diff = a.start-b.start;
    for (int i = 0; i < a.size(); ++i) {
        if (a.val[i] != b.val[i+diff])
            return false;
    }
    return true;
}

const int MAX_K = 2009;

mod_num tab[MAX_K][MAX_K][2];
bool comp[MAX_K];

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin >> n;
    std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
    {
        std::string input;
        getline(std::cin, input);
        parser p(input);
        p.parse();
    }
    std::sort(++clauses.begin(), clauses.end(),
              [](const clause& a, const clause& b) {
                  return a.end < b.end || (a.end == b.end && a.start > b.start);
              });
    mod_num result = modpow(2, n);
    int i = 1;
    for (int z = 1; z < clauses.size(); ++z) {
        const clause& c = clauses[z];
        tab[i][1][0] = modpow(2, n-c.size());
        tab[i][1][1] = tab[i-1][1][1]+tab[i-1][1][0];
        int q;
        bool uniq = true;
        for (q = i-1; q > 0; --q) {
            const clause& c2 = clauses[q];
            if (c2.end <= c.start) {
                break;
            }
            if (c2.start >= c.start && check_in(c2, c)) {
                uniq = false;
                break;
            }
            comp[q] = check_overlap(c, c2);
        }
        if (!uniq) {
            continue;
        }
        //std::cout << c << std::endl;
        //std::cout << i << " q(" << q << ") ";
        //std::cout << tab[i][1][0];
        for (int j = 2; j <= i; ++j) {
            tab[i][j][1] = tab[i-1][j][1]+tab[i-1][j][0];
        }
        for (int j = 2; j <= i; ++j) {
            for (int k = q+1; k < i; ++k) {
                if (comp[k]) {
                    tab[i][j][0] += tab[k][j-1][0]/modpow(2, c.size()-(clauses[k].end-c.start));
                }
            }
            tab[i][j][0] += tab[q+1][j-1][1]/modpow(2, c.size());
            //std::cout << " " << tab[i][j][0];
            //std::cout << "=" << tab[q+1][j-1][1] << "/" << modpow(2, c.size());
        }
        if (i < z) {
            clauses[i] = clauses[z];
        }
        ++i;
        //std::cout << std::endl;
    }
    int m = i-1;
    /* for (int i = 1; i <= m; ++i) {
     std::cout << " " << tab[m][i][0]+tab[m][i][1];
    }
    std::cout << std::endl; */
    for (int i = 1; i <= m; i += 2) {
        result -= tab[m][i][0]+tab[m][i][1];
    }
    for (int i = 2; i <= m; i += 2) {
        result += tab[m][i][0]+tab[m][i][1];
    }
    std::cout << result << std::endl;
}