void multiply(vector < uint > a, vector < uint > b, vector < uint > &res) {
    if (a.size() == 1) {
        res = b;
        fori(b.size()) res[i] *= a[0];
        return ;
    }
    if (b.size() == 1) {
        res = a;
        fori(a.size()) res[i] *= b[0];
        return ;
    }
    if (a.size() + b.size() <= 10) {
        res.resize(a.size() + b.size() - 1);
        for (int i = 0; i < a.size(); i++) {
            for (int j = 0; j < b.size(); j++) {
                res[i + j] += (a[i] * b[j]);
            }
        }
        return ;
    }
    int cnt1 = a.size(), cnt2 = b.size();
    if (a.size() > b.size()) {
        while (a.size() != b.size()) b.pb(0);
    } else if (a.size() < b.size()) {
        while (a.size() != b.size()) a.pb(0);
    }
    if (a.size() != b.size()) {
        //cout << cnt1 << " " << cnt2 << "\n";
        //cout << a.size() << " " << b.size() << "\n";
        while (true) {}
        exit(0);
    }
    int m = (a.size() + 1) / 2;
    vector < uint > a0, a1, b0, b1;
    vector < uint > a0b0, a1b1;
    a0.resize(m);
    b0.resize(m);
    a1.resize(a.size() - m);
    b1.resize(b.size() - m);
    for (int i = 0; i < m; i++) a0[i] = a[i];
    for (int i = m; i < a.size(); i++) a1[i - m] = a[i];

    for (int i = 0; i < m; i++) b0[i] = b[i];
    for (int i = m; i < b.size(); i++) b1[i - m] = b[i];
    multiply(a0, b0, a0b0);
    multiply(a1, b1, a1b1);
    sum(a0, a1);
    sum(b0, b1);
    vector < uint > keks1;
    multiply(a0, b0, keks1);
    //for (auto c: keks1) cout << c << " ";
    //cout << "\n";
    substraction(keks1, a0b0);
    substraction(keks1, a1b1);
    res.resize(a.size() + b.size() - 1);
    for (int i = 0; i < a0b0.size(); i++) {
        res[i] += a0b0[i];
    }
    for (int i = m; i - m < keks1.size(); i++) {
        res[i] += keks1[i - m];
    }
    for (int i = 2 * m; i - 2 * m < a1b1.size(); i++) {
        res[i] += a1b1[i - 2 * m];
    }
    while (true) {
        if (res.back() == 0) res.pop_back();
        else break;
    }
    return ;
}