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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

bool DEBUGER = false;

struct Node
{
    long long int begin, end;
    vector<Node*> children;
};

void sortVector(vector<Node*> &vectorToSort)
{
    sort(vectorToSort.begin(), vectorToSort.end(),
         [](const Node* a, const Node* b) -> bool
         {
             return (a->end - a->begin) > (b->end - b->begin);
         });
}

//void addInterval(Node* root, Node* toAdd)
//{
////    for(int i = 0; i < root->children.size(); i++)
////    {
////
////    }
//    if(DEBUGER)cout<<"brzegi roota "<<root->begin<<", "<<root->end<<" oraz brzegi drugiego "<<toAdd->begin<< ", " << toAdd->end<<endl;
//    if(toAdd->begin >= toAdd->end or (toAdd->begin == root->begin and toAdd->end == root->end))
//        return;
//    if(root->children.empty()) {
//        toAdd->begin = max(toAdd->begin, root->begin);
//        toAdd->end = min(toAdd->end, root->end);
//        if(DEBUGER)cout<<"-1"<<endl;
//        root->children.push_back(toAdd);
//        return;
//    }
//
//    int i = 0;
//    auto iter =  root->children.begin();
//    while(root->children[i]->end <= toAdd->begin)
//    {
//        i++;
//        if(root->children.size() == i)
//        {
//            if(DEBUGER)cout<<"0"<<endl;
//            root->children.push_back(toAdd);
//            return;
//        }
//        iter++;
//    }
//    if(toAdd->end <= root->children[i]->begin)
//    {
////        cout<<"tutaj"<<toAdd->begin<<" " << toAdd->end<<endl;
//        if(DEBUGER)cout<<"1"<<endl;
//        root->children.insert(iter, toAdd);
//        return;
//    }
//    if(root->children[i]->end >= toAdd->end and root->children[i]->begin <= toAdd->begin)
//    {
////        cout<<" a jednak tutaj"<<toAdd->begin<<" " << toAdd->end<<endl;
//        if(DEBUGER)cout<<"2"<<endl;
//        addInterval(root->children[i], toAdd);
//        return;
//    }
//    if(toAdd->begin < root->children[i]->begin)
//    {
//        if(DEBUGER)cout<<"3"<<endl;
//        Node* pom = new Node;
//        pom->begin = toAdd->begin;
//        pom->end = root->children[i]->begin;
//        toAdd->begin = pom->end;
//        addInterval(root->children[i], toAdd);
//        root->children.insert(iter, pom);
//        return;
//    }
//
//
//    Node* newNode = new Node;
//    newNode->begin = toAdd->begin;
//    newNode->end = root->children[i]->end;
//    addInterval(root->children[i], newNode);
//    toAdd->begin = root->children[i]->end;
//    i++;
//    if(i == root->children.size())
//    {
//        if(DEBUGER)cout<<"4"<<endl;
//        root->children.push_back(toAdd);
//        return;
//    }
//    iter++;
//    if(toAdd->begin <= root->children[i]->begin){
//        if(DEBUGER)cout<<"5"<<endl;
//        Node* secondNewNode = new Node;
//        secondNewNode->begin = toAdd->begin;
//        secondNewNode->end = min(root->children[i]->begin, toAdd->end);
//        toAdd->begin = root->children[i]->begin;
//        addInterval(root->children[i], toAdd);
//        if(secondNewNode->begin < secondNewNode->end)
//            root->children.insert(iter, secondNewNode);
//        return;
//    }
//
//}

void addInterval(Node* root, Node* toAdd, int whereStart=0)
{
    if(DEBUGER)cout<<"brzegi roota "<<root->begin<<", "<<root->end<<" oraz brzegi drugiego "<<toAdd->begin<< ", " << toAdd->end<<endl;
    if(toAdd->begin >= toAdd->end or (toAdd->begin == root->begin and toAdd->end == root->end))
        return;
    if(root->children.empty()) {
        toAdd->begin = max(toAdd->begin, root->begin);
        toAdd->end = min(toAdd->end, root->end);
        if(DEBUGER)cout<<"-1"<<endl;
        root->children.push_back(toAdd);
        return;
    }

    int i = whereStart;
    auto iter =  root->children.begin() + whereStart;
    while(root->children[i]->end <= toAdd->begin)
    {
        i++;
        if(root->children.size() == i)
        {
            if(DEBUGER)cout<<"0"<<endl;
            root->children.push_back(toAdd);
            return;
        }
        iter++;
    }

    if(toAdd->begin < root->children[i]->begin)
    {
        Node* pom = new Node;
        pom->end = toAdd->end;
        pom->begin = min(root->children[i]->begin, toAdd->end);
        toAdd->end = min(root->children[i]->begin, toAdd->end);
        addInterval(root, pom, i);
        root->children.insert(iter, toAdd);
        return;
    }
    Node* pom = new Node;
    pom->end = toAdd->end;
    pom->begin = min(root->children[i]->end, toAdd->end);
    toAdd->end = min(root->children[i]->end, toAdd->end);
    addInterval(root->children[i], toAdd);
    addInterval(root, pom, i);
//    root->children.insert(iter, toAdd);
}

void printTree(Node* root)
{
    if(DEBUGER)cout<<root->begin<<' '<<root->end<<" number of children: "<<root->children.size()<<endl;
    for(auto & i : root->children)
        printTree(i);
}

long long int maxInterval(Node* root)
{
    long long int maxRootInterval = root->end - root->begin;
    long long int result = 0;
    for(int i = 0; i < root->children.size(); i++)
    {
        result = max(result, maxInterval(root->children[i]));
        maxRootInterval -= (root->children[i]->end - root->children[i]->begin);
    }
    if(DEBUGER)cout<<root->begin<<" "<<root->end<<" "<<maxRootInterval<<endl;
    return max(maxRootInterval, result);
}

long long int algorithmForOneAx(vector<Node*> nodes, long long int size)
{
    Node* nodeX = new Node;
    nodeX->begin = 0;
    nodeX->end = size;

    sortVector(nodes);

    for(auto & node : nodes) {
        addInterval(nodeX, node);
        if(DEBUGER)printTree(nodeX);
        if(DEBUGER)cout<<"-------------------------------------------------"<<endl;
    }
//    printTree(nodeX);
    return maxInterval(nodeX);
}

int main() {
    ios_base::sync_with_stdio(false);
    long long int numberOfAnimals, sizeX, sizeY;

    cin >> numberOfAnimals >> sizeX >> sizeY;


    vector<Node*> nodeX;
    vector<Node*> nodeY;

    for(int i = 0; i < numberOfAnimals; i++)
    {
        long long int x1, x2, y1, y2;
        cin>> x1 >> y1 >> x2 >> y2;
        Node* newNode = new Node;
        newNode->end = max(x1, x2);
        newNode->begin = min(x1, x2);
        nodeX.push_back(newNode);
        newNode = new Node;
        newNode->begin = min(y1, y2);
        newNode->end = max(y1, y2);
        nodeY.push_back(newNode);
    }
    long long int ile = algorithmForOneAx(nodeX, sizeX);
    long long int ile2 = 0;
    if(!DEBUGER)
    {
        ile2 = algorithmForOneAx(nodeY, sizeY);
        long long int maxField = ile * ile2;
        cout<<maxField<<endl;
    }
    if(DEBUGER)cout<<ile<<" " << ile2<<endl;
//    long long int maxField = algorithmForOneAx(nodeY, sizeY);

    return 0;
}