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#define make_pair mp
#define emplace_back pb
#include <bits/stdc++.h>
using namespace std;
const int N = 5e5 + 3, D = (1<<22) + 5, pods = (1<<21) - 1, INF = 2e9 + 10;
int n, X, Y, xx[N], xxx[N], yy[N], yyy[N];
map<int, int> mapa;
vector<int> tab[2*N];
int ansx, ansy, d[D];

void add(int x, int val) {
	x += pods;
	while(x) {
		d[x] += val;
		x /= 2;
	}
}

int suma(int x, int y) {
	if(x > y) return 1;
	x += pods;
	y += pods;
	int ans = d[x];
	if(x != y) ans += d[y];
	while(x / 2 != y / 2) {
		if(x % 2 == 0) ans += d[x+1];
		if(y % 2 == 1) ans += d[y-1];
		x /= 2;
		y /= 2;
	}
	return ans;
}

void clear() {
	for(int i=0;i<D;i++) d[i] = 0;
}

int pos[N][4];
int cnt[N];
int what[4*N];
int m;

void add_num(int id, int x) {
	pos[id][cnt[id]] = x;
	cnt[id]++;
}

void swap_num(int id) {
	for(int i=0;i<3;i++) swap(pos[id][i], pos[id][i+1]);
}

void perform() {
	pos[0][0] = INF;
	pos[0][1] = INF;
	clear();
	for(int i=1;i<=n;i++)  sort(pos[i], pos[i] + 4);

	for(int i=1;i<=n;i++) {
		int x = pos[i][0];
		int y = pos[i][1];
		add(x, 1);
		add(y, -1);
	}

	for(int i=1;i<=m/2;i++) {
		if(i != 1) ansx = max(ansx, what[i] - what[i-1]);
		int x = 0;
		for(auto &z : tab[i]) if(pos[z][1] < pos[x][1]) x = z;
		int y = pos[x][1];
		int sum = suma(i + 1, y - 1);
		if(sum == 0) {
			ansx = max(ansx, what[i+1] - what[i] + what[y] - what[y-1]);
		}

		for(auto x : tab[i]) {
			int z = pos[x][1];
			int zz = pos[x][2];
			add(z, 2);
			swap_num(x);
			add(zz, -1);
		}
	}

	for(int i=1;i<=n;i++) cnt[i] = 0;
	ansx = max(ansx, what[m/2+1] - what[m/2]);
}

int main()
{
	scanf("%d%d%d", &n, &X, &Y);
	for(int i=1;i<=n;i++) {
		scanf("%d%d", &xxx[i], &yyy[i]);	
		scanf("%d%d", &xx[i], &yy[i]);
	}

	for(int i=1;i<=n;i++) {
		mapa[xxx[i]] = 0;
		mapa[xx[i]] = 0;
		mapa[xxx[i] + X] = 0;
		mapa[xx[i] + X] = 0;
	}
	m = mapa.size();

	int wsk = 0;
	for(auto &it : mapa) {
		wsk++;
		it.second = wsk;
		what[wsk] = it.first;
	}

	for(int i=1;i<=n;i++) {
		tab[mapa[xxx[i]]].pb(i);
		tab[mapa[xx[i]]].pb(i);
		add_num(i, mapa[xx[i]]);
		add_num(i, mapa[xxx[i]]);
		add_num(i, mapa[xx[i] + X]);
		add_num(i, mapa[xxx[i] + X]);
	}

	perform();
	swap(ansx, ansy);
	mapa.clear();
	for(int i=1;i<=m;i++) tab[i].clear();
	for(int i=1;i<=n;i++) {
		mapa[yyy[i]] = 0;
		mapa[yy[i]] = 0;
		mapa[yyy[i] + Y] = 0;
		mapa[yy[i] + Y] = 0;
	}
	m = mapa.size();

	wsk = 0;
	for(auto &it : mapa) {
		wsk++;
		it.second = wsk;
		what[wsk] = it.first;
	}

	for(int i=1;i<=n;i++) {
		tab[mapa[yyy[i]]].pb(i);
		tab[mapa[yy[i]]].pb(i);
		add_num(i, mapa[yy[i]]);
		add_num(i, mapa[yyy[i]]);
		add_num(i, mapa[yy[i] + Y]);
		add_num(i, mapa[yyy[i] + Y]);
	}
	perform();

	long long ans = (long long)ansx * (long long)ansy;
	printf("%lld", ans);

	return 0;
}