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#include <bits/stdc++.h>

using namespace std;

#define PB push_back
#define SZ(x) int((x).size())
#define REP(i, n) for(int i=0,_=(n);i<_;++i)
#define FOR(i, a, b) for(int i=(a),_=(b);i<=_;++i)
#define FORD(i, a, b) for(int i=(a),_=(b);i>=_;--i)

#ifdef DEBUG
#define DEB(x) (cerr << x)
#else
#define DEB(x)
#endif

typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pii;

const int INF = 1e9 + 9;

template<typename T>
struct Point {
    T x, y;

    Point() {}

    Point(T _x, T _y) :
            x(_x), y(_y) {}

    Point rotated(double fi) const {
        return Point(x * cos(fi) - y * sin(fi), x * sin(fi) + y * cos(fi));
    }

    void rotate(double fi) {
        (*this) = this->rotated(fi);
    }

    void operator+=(const Point &p) {
        x += p.x, y += p.y;
    }

    double norm() const {
        return sqrt(x * x + y * y);
    }

    double norm_squared() const {
        return x * x + y * y;
    }

    Point operator-(const Point &p) const {
        return Point(x - p.x, y - p.y);
    }

    double distance_to(const Point &p) const {
        return (*this - p).norm();
    }

    double distance_to_squared(const Point &p) const {
        return (*this - p).norm_squared();
    }

    double angle() const {
        return atan2(y, x);
    }

    double angle2() const { // ??? result always positive?
        double k = atan2(y, x);
        if (k < 0) {
            k += 0.5 * M_PI;
        }
        return k;
    }

    void operator*=(double a) {
        x *= a, y *= a;
    }

    Point operator*(double a) const {
        Point result = *this;
        result *= a;
        return result;
    }

    Point operator+(const Point &p) const {
        return Point(x + p.x, y + p.y);
    }

    bool operator<(const Point &p) const {
        if (x == p.x) {
            return y < p.y;
        }
        return x < p.x;
    }

    bool operator==(const Point &p) const {
        return x == p.x && y == p.y;
    }
};

template<typename T>
std::ostream &operator<<(std::ostream &os, const Point<T> &p) {
    return os << "Point(" << p.x << ", " << p.y << ")";
}

template<typename T>
T my_abs(const T &x) {
    if (x < 0) {
        return -x;
    }
    return x;
}


template<typename T>
struct Segment : public pair<Point<T>, Point<T>> { // Can be used as rectangle as well.
    Segment(const Point<T> &p1, const Point<T> &p2) :
            pair<Point<T>, Point<T>>(p1, p2) {
    }

    T area_of_rectangle_between() const { //rectangle
        T diff_x = my_abs(this->first.x - this->second.x);
        T diff_y = my_abs(this->first.y - this->second.y);
        return diff_x * diff_y;
    }

    bool is_forward() const {
        return this->second.x > this->first.x && this->second.y > this->first.y;
    }

    vector <Segment<T>>
    split_to_rectangles_by_rolling_over_torus(bool roll_over_x, bool roll_over_y, T max_x, T max_y) const { //rectangle
        vector <T> xs, ys;
        if (roll_over_x) {
            xs.PB(0);
            xs.PB(min(this->first.x, this->second.x));
            xs.PB(max(this->first.x, this->second.x));
            xs.PB(max_x);
        } else {
            xs.PB(min(this->first.x, this->second.x));
            xs.PB(max(this->first.x, this->second.x));
        }
        if (roll_over_y) {
            ys.PB(0);
            ys.PB(min(this->first.y, this->second.y));
            ys.PB(max(this->first.y, this->second.y));
            ys.PB(max_y);
        } else {
            ys.PB(min(this->first.y, this->second.y));
            ys.PB(max(this->first.y, this->second.y));
        }
        vector <Segment> result;
        for (int i = 0; i < SZ(xs); i += 2) {
            for (int j = 0; j < SZ(ys); j += 2) {
                result.PB(Segment(Point(xs[i], ys[j]), Point(xs[i + 1], ys[j + 1])));
            }
        }
        return result;
    }

    Segment rectangles_intersection(const Segment &rectangle) { // rectangle
        T left_x1 = min(this->first.x, this->second.x);
        T left_x2 = min(rectangle.first.x, rectangle.second.x);
        T right_x1 = max(this->first.x, this->second.x);
        T right_x2 = max(rectangle.first.x, rectangle.second.x);
        T bottom_y1 = min(this->first.y, this->second.y);
        T bottom_y2 = min(rectangle.first.y, rectangle.second.y);
        T top_y1 = max(this->first.y, this->second.y);
        T top_y2 = max(rectangle.first.y, rectangle.second.y);
        return Segment(
                Point(max(left_x1, left_x2), max(bottom_y1, bottom_y2)),
                Point(min(right_x1, right_x2), min(top_y1, top_y2))
        );
    }
};

template<typename T>
std::ostream &operator<<(std::ostream &os, const Segment<T> &p) {
    return os << "Segment(" << p.first << ", " << p.second << ")";
}

ll solve_one(const vector <Segment<ll>> &input_segments, ll max_x, ll max_y) {
    vector <Segment<ll>> result;
    result.PB(Segment(Point<ll>(0, 0), Point<ll>(max_x, max_y)));
    for (auto &s: input_segments) {
        ll best_area = 0;
        vector <Segment<ll>> chosen;
        REP(bx, 2) {
            REP(by, 2) {
//                DEB("bxy: " << bx << ", " << by << "\n");
                auto rectangles = s.split_to_rectangles_by_rolling_over_torus(bool(bx), bool(by), max_x, max_y);
                ll total_area = 0;
                for (auto &rectangle : rectangles) {
//                    DEB(rectangle << ", ");
                    total_area += rectangle.area_of_rectangle_between();
                }
//                DEB("\n");
//                DEB("total_area: " << total_area << "\n");
                vector <Segment<ll>> intersected;
                ll intersected_area = 0;
                for (auto &rectangle: rectangles) {
                    for (auto &other: result) {
                        auto inter = rectangle.rectangles_intersection(other);
                        if (inter.is_forward()) {
                            intersected.PB(inter);
                            intersected_area += inter.area_of_rectangle_between();
                        }
                    }
                }
                if (intersected_area > best_area) {
                    best_area = intersected_area;
                    chosen = intersected;
                }
            }
        }
        result = chosen;
    }
    ll result_area = 0;
    for (auto &rectangle: result) {
        result_area += rectangle.area_of_rectangle_between();
    }
    return result_area;
}

void inline one() {
    int n;
    ll max_x, max_y;
    cin >> n >> max_x >> max_y;

    vector <Segment<ll>> input_segments;
    REP (i, n) {
        Point<ll> p1, p2;
        cin >> p1.x >> p1.y >> p2.x >> p2.y;
        Segment<ll> s(p1, p2);
        if (!s.is_forward()) {
            s = Segment<ll>(p2, p1);
        }
//        DEB(s << "\n");
//        DEB("area: " << s.area_of_rectangle_between() << "\n");
        input_segments.PB(s);
    }

    sort(input_segments.begin(), input_segments.end());

    ll result_area = solve_one(input_segments, max_x, max_y);

    REP(i, 4) {
        random_shuffle(input_segments.begin(), input_segments.end());
        ll area = solve_one(input_segments, max_x, max_y);
        DEB("random_area: " << area << "\n");
        result_area = max(result_area, area);
    }

    cout << result_area << "\n";
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    //int z; cin >> z; while(z--)
    one();
}