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#include <bits/stdc++.h>

using namespace std;

int calc(int m, multiset<int> & from, multiset<int> & to, multiset<pair<int, int> > & bans) {
    int s1 = 0;
    int s2 = m;
    if (!from.empty()) {
        s1 = *from.rbegin();
        s2 = *to.begin();
        if (s2 <= s1) {
            return 0;
        }
    }

    int ans = 0;
    int banto = s1;
    for (auto p : bans) {
        int b1 = p.first;
        if (b1 >= s2) {
            break;
        }
        int b2 = p.second;
        if (b1 > banto) {
            ans += b1 - banto;
        }
        banto = max(banto, b2);
    }

    // do [banto, s2]
    if (s2 > banto) {
        ans += s2 - banto;
    }

    return ans;
}

int solve(int m, vector<pair<int, int> > & v) {
    int n = v.size();
    vector<pair<int, int> > events;
    for (auto p : v) {
        events.push_back(p);
        events.push_back({p.second, p.first});
    }
    sort(events.begin(), events.end());
    multiset<int> from;
    multiset<int> to;
    multiset<pair<int, int> > bans;
    for (auto p : v) {
        bans.insert(p);
    }

    int ans = calc(m, from, to, bans);
    for (auto e : events) {
        if (e.first < e.second) {
            bans.erase(bans.find(e));
            from.insert(e.first);
            to.insert(e.second);
        } else {
            to.erase(to.find(e.first));
            from.erase(from.find(e.second));
            bans.insert({e.second, e.first});
        }
        int cand = calc(m, from, to, bans);
        ans = max(ans, cand);
    }

    return ans;
}

int main() {
    ios_base::sync_with_stdio(false);
    cout.precision(15);
    cout << fixed;
    cin.tie(0);

    int n, x, y;
    cin >> n >> x >> y;
    vector<pair<int, int> > xx;
    vector<pair<int, int> > yy;
    for (int i = 0; i < n; i++) {
        int x1, y1, x2, y2;
        cin >> x1 >> y1 >> x2 >> y2;
        if (x1 > x2) swap(x1, x2);
        if (y1 > y2) swap(y1, y2);
        xx.push_back({x1, x2});
        yy.push_back({y1, y2});
    }

    long long ansx = solve(x, xx);
    long long ansy = solve(y, yy);

    cout << ansx * ansy << endl;

    return 0;
}