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#include <iostream>
#include <vector>

using namespace std;

typedef long long int lint;

int X, Y;

class Rect {
public:
    lint x1, y1, x2, y2;

    Rect(lint _x1, lint _y1, lint _x2, lint _y2) :
        x1(min(_x1, _x2)),
        y1(min(_y1, _y2)),
        x2(max(_x1, _x2)),
        y2(max(_y1, _y2)) {
    }

    lint surface() const {
        return (x2 - x1) * (y2 - y1);
    }

    bool isDegenerated() const {
        return x2 <= x1 || y2 <= y1;
    }

    Rect intersect(const Rect& other) const {
        lint x = max(x1, other.x1);
        lint X = min(x2, other.x2);
        lint y = max(y1, other.y1);
        lint Y = min(y2, other.y2);
        if (x < X && y < Y) {
            return Rect(x, y, X, Y);
        } else {
            return Rect(0, 0, 0, 0);
        }
    }
};

class DisjointRects {
public:
    vector<Rect> rects;

    DisjointRects()=default;
    DisjointRects(const DisjointRects&)=delete;
    DisjointRects(DisjointRects&& temp)
        : rects(move(temp.rects))
    {
    }

    DisjointRects& operator=(const DisjointRects&)=delete;

    void addRect(Rect r) {
        if (!r.isDegenerated()) {
            rects.push_back(r);
        }
    }

    bool empty() const {
        return rects.empty();
    }

    lint surface() const {
        lint sum = 0;
        for (const Rect& r: rects) {
            sum += r.surface();
        }
        return sum;
    }

    DisjointRects intersect(const DisjointRects& other) const {
        DisjointRects res;
        for (const Rect& r: other.rects) {
            for (const Rect& q: rects) {
                res.addRect(r.intersect(q));
            }
        }
        return res;
    }
};

class Possiblites {
public:
    vector<DisjointRects> possibilites;

    Possiblites()=default;
    Possiblites(const Possiblites&) = delete;
    Possiblites(Possiblites&& temp)
        : possibilites(move(temp.possibilites))
    {
    }

    Possiblites& operator=(const Possiblites&) = delete;
    Possiblites& operator=(Possiblites&& temp) {
        this->possibilites = move(temp.possibilites);
        return *this;
    }

    void addPossibility(DisjointRects&& poss) {
        if (poss.empty()) {
            return;
        }
        if (poss.rects.size() == 1 && poss.surface() == 1) {
            return;
        }
        possibilites.push_back(move(poss));
    }

    bool empty() {
        return possibilites.empty();
    }

    lint worst() const {
        lint m = X*Y;
        for (const DisjointRects& poss: possibilites) {
            lint s = poss.surface();
            if (s < m) {
                m = s;
            }
        }
        return m;
    }

    lint best() const {
        lint M = 0;
        for (const DisjointRects& poss: possibilites) {
            lint s = poss.surface();
            if (s > M) {
                M = s;
            }
        }
        return M;
    }

    Possiblites addTerritory(lint x1, lint y1, lint x2, lint y2) const {
        const vector<DisjointRects>& terrInters = createTerritoryInterpretations(x1, y1, x2, y2);
        Possiblites res;
        for (const DisjointRects& terrInter: terrInters) {
            for (const DisjointRects& poss: possibilites) {
                res.addPossibility(terrInter.intersect(poss));
            }
        }
        return res;
    }

    vector<DisjointRects> createTerritoryInterpretations(lint x1, lint y1, lint x2, lint y2) const {
        vector<DisjointRects> terrInters;
        Rect b(x1, y1, x2, y2);

        DisjointRects inter1;
        inter1.addRect(Rect(0, 0, b.x1, b.y1));
        inter1.addRect(Rect(b.x2, b.y1, X, 0));
        inter1.addRect(Rect(b.x2, b.y2, X, Y));
        inter1.addRect(Rect(0, Y, b.x1, b.y2));
        terrInters.push_back(move(inter1));

        DisjointRects inter2;
        inter2.addRect(Rect(b.x1, 0, b.x2, b.y1));
        inter2.addRect(Rect(b.x1, b.y2, b.x2, Y));
        terrInters.push_back(move(inter2));

        DisjointRects inter3;
        inter3.addRect(Rect(0, b.y1, b.x1, b.y2));
        inter3.addRect(Rect(b.x2, b.y1, X, b.y2));
        terrInters.push_back(move(inter3));

        DisjointRects inter4;
        inter4.addRect(Rect(b.x1, b.y1, b.x2, b.y2));
        terrInters.push_back(move(inter4));

        return terrInters;
    }

    static Possiblites wholePlanet() {
        Possiblites possibilites;
        DisjointRects rects;
        rects.addRect(Rect(0, 0, X, Y));
        possibilites.addPossibility(move(rects));
        return possibilites;
    }
};

int main()
{
    ios_base::sync_with_stdio(false);
    int n; cin >> n >> X >> Y;
    Possiblites possibilities = Possiblites::wholePlanet();
    while (n--) {
        int x1, y1, x2, y2;
        cin >> x1 >> y1 >> x2 >> y2;
        possibilities = possibilities.addTerritory(x1, y1, x2, y2);
        if (possibilities.empty()) {
            break;
        }
        //cout << possibilities.possibilites.size() << endl;
        //cout << possibilities.worst() << " " << possibilities.best() << endl;
    }
    if (possibilities.empty()) {
        cout << 1 << endl;
    } else {
        cout << possibilities.best() << endl;
    }
    return 0;
}