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#define _CRT_SECURE_NO_WARNINGS 1
#define _WINSOCK_DEPRECATED_NO_WARNINGS 1

#include <cstdio>
#include <algorithm> 
#include <vector>
#include <stack>
#include <map>
#include <set>
#include <unordered_set>

using namespace std;

struct Pair
{
	int coordinate;
	int species;
};
struct Interval
{
	set<int> species;
	int score;

	Interval()
	{

	}

	Interval(int s, int l)
	{
		this->species.insert(s);
		this->score = l;
	}

	bool Contains(int needle)
	{	
		return (species.find(needle) != (species.end()));
	}
};

bool Sorter(Pair const& lhs, Pair const& rhs)
{
	if (lhs.coordinate == rhs.coordinate)
	{
		return lhs.species < rhs.species;
	}
	return lhs.coordinate < rhs.coordinate;
}
int findMax(vector<Pair> const& x, int n, int X)
{
	vector<int> cx(n + 1);
	vector<Interval> stack(n + 13);
	int stop = 0;	
	Interval start(-1, 0);
	stack[stop] = start;

	int c = 0;
	int maxValue = 0;

	for(int i = 0; i < x.size(); ++i)
	{
		int coordinate = x[i].coordinate;
		int species = x[i].species;
		int delta = coordinate - c;
		stack[stop].score += delta;
		maxValue = max(maxValue, stack[stop].score);
		cx[species]++;

		if (cx[species] == 2)
		{			
			int si = stop;
			while (stack[si].Contains(species) == false)
			{
				si--;
			}
			stack[si].species.erase(species);
			int diff = stop - si;

			if (diff > 10)
			{
				int maxsi = si;
				int maxsiCount = 0;
				for (int j = si; j <= stop; ++j)
				{
					if (stack[j].species.size() > maxsiCount)
					{
						maxsiCount = stack[j].species.size();
						maxsi = j;
					}
				}				

				for (int j = si; j <= stop; ++j)
				{
					if (j != maxsi)
					{
						stack[maxsi].species.insert(stack[j].species.begin(), stack[j].species.end());
						stack[j].species = set<int>();
					}
				}
				
				stop = si;
				stack[stop].species.swap(stack[maxsi].species);
				stack[stop].score = 0;
			}
			else
			{
				for(int j = si; j<= stop; ++j)
				{					
					stack[j].score = 0;
				}
			}

			while (stack[stop].species.size() == 0 && stop > 0)
			{
				stack[stop].species = set<int>();
				stop--;
			}
		}
		else
		{
			Interval ns(species, 0);
			stack[++stop] = ns;
		}

		c = coordinate;
	}
	int delta = X - c;
	stack[stop].score += delta;
	maxValue = max(maxValue, stack[stop].score);
	
	return maxValue;
}


int main()
{
	int n, X, Y;

	scanf("%d%d%d", &n, &X, &Y);
	vector<Pair> x(n * 2);
	vector<Pair> y(n * 2);

	for (long i = 0; i < n; ++i)
	{
		int x1, y1, x2, y2;
		scanf("%d%d%d%d", &x1, &y1, &x2, &y2);

		x[i * 2].species = i + 1;
		x[i * 2].coordinate = x1;
		x[i * 2 + 1].species = i + 1;
		x[i * 2 + 1].coordinate = x2;
		y[i * 2].species = i + 1;
		y[i * 2].coordinate = y1;
		y[i * 2 + 1].species = i + 1;
		y[i * 2 + 1].coordinate = y2;
	}

	std::sort(x.begin(), x.end(), &Sorter);
	std::sort(y.begin(), y.end(), &Sorter);

	long long maxX = findMax(x, n, X);
	long long maxY = findMax(y, n, Y);

	long long result = maxX * maxY;

	printf("%lld", result);
}