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#include <cstdio>
#include <cassert>
#include <algorithm>
#include <vector>
#include <queue>

using namespace std;

unsigned int x, y, n;

class true_rect {
public:
        unsigned int x1, y1, x2, y2;
        unsigned long long area;

        true_rect(unsigned int a1, unsigned int b1, unsigned int a2, unsigned int b2);
        true_rect intersect(true_rect &tr);
        void print();
};

true_rect::true_rect(unsigned int a1, unsigned int b1, unsigned int a2, unsigned int b2)
{
        x1 = min(a1, a2);
        x2 = max(a1, a2);
        y1 = min(b1, b2);
        y2 = max(b1, b2);
        area = (static_cast<long long>(x2-x1)) * (static_cast<long long>(y2-y1));
//        printf("(%u, %u) - (%u, %u) - area=%llu\n", x1, y1, x2, y2, area);
}

true_rect true_rect::intersect(true_rect &tr)
{
        if (this->x1 >= tr.x2 || tr.x1 >= this->x2)
                return true_rect(0, 0, 0, 0);
        if (this->y1 >= tr.y2 || tr.y1 >= this->y2)
                return true_rect(0, 0, 0, 0);

        return true_rect( max(this->x1, tr.x1), max(this->y1, tr.y1), min(this->x2, tr.x2), min(this->y2, tr.y2) );
}

void true_rect::print()
{
        printf("    (%u, %u) - (%u, %u) - (%llu)\n", x1, y1, x2, y2, area);
}

class region {
public:
        vector<true_rect> v;
        long long area;
        int nr_processed;

        region() {};
        region(true_rect tr);
        region* intersect(true_rect r);
        region* intersect(region *r);
        void add_true_rect(true_rect tr);
        void print_area();
        void print();
};

class region_cmp {
public:
        bool operator()(const region *l, region *r)
        {
                if (l->area == r->area) {
                        return l->nr_processed < r->nr_processed;
                }
                return l->area < r->area;
        }
};

region::region(true_rect tr)
{
        v.push_back(tr);
        area = tr.area;
}

region* region::intersect(true_rect r)
{
        region *reg = new region();
        
        reg->area = 0;
        for(vector<true_rect>::iterator it = this->v.begin(); it != this->v.end(); ++it) {
                true_rect tr = it->intersect(r);
                if (tr.area != 0) {
                        reg->v.push_back(tr);
                        reg->area += tr.area;
                }
        }
        if (reg->area == 0) {
                delete reg;
                return nullptr;
        }
        return reg;
}

region* region::intersect(region *r)
{
        region *reg = new region();
        
        reg->area = 0;
        for(vector<true_rect>::iterator it = r->v.begin(); it != r->v.end(); ++it) {
                region *tmp = this->intersect(*it);
                if (tmp == nullptr) {
                        continue;
                }
                for(vector<true_rect>::iterator it2 = tmp->v.begin(); it2 != tmp->v.end(); ++it2) {
                        reg->v.push_back(*it2);
                        reg->area += it2->area;
                }
                delete tmp;
        }
        if (reg->area == 0) {
                delete reg;
                return nullptr;
        }
        return reg;
}

void region::add_true_rect(true_rect tr)
{
        v.push_back(tr);
        area += tr.area;
}

void region::print_area()
{
        printf("area = %lld\n", this->area);
}

void region::print()
{
        for(vector<true_rect>::iterator it = this->v.begin(); it != this->v.end(); ++it) {
                (*it).print();
        }
}

class rect {
public:
        vector<region*> v;

        rect(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2);
        void print();
};

rect::rect(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2)
{
        region *a, *b, *c, *d;

        a = new region ( true_rect(x1, y1, x2, y2) );
        b = new region ( true_rect(x2, y1, x, y2) );
        c = new region ( true_rect(x1, y2, x2, y) );
        d = new region ( true_rect(x2, y2, x, y) );

        if (x1 > 0) {
                b->add_true_rect( true_rect(0, y1, x1, y2) );
        }
 
        if (y1 > 0) {
                c->add_true_rect( true_rect(x1, 0, x2, y1) );
        }
        
        if (x1 > 0 && y1 > 0) {
                d->add_true_rect( true_rect(0, 0, x1, y1) );
        }

        if (x1 > 0) {
                d->add_true_rect( true_rect(0, y2, x1, y) );
        }

        if (y1 > 0) {
                d->add_true_rect( true_rect(x2, 0, x, y1) );
        }
        v.push_back(a);
        v.push_back(b);
        v.push_back(c);
        v.push_back(d);
}

void rect::print()
{
        printf("area a=%llu, b=%llu, c=%llu, d=%llu\n", v[0]->area, v[1]->area, v[2]->area, v[3]->area);
}

priority_queue<region*, vector<region*>, region_cmp> make_initial_q(rect *r1, rect *r2)
{
        priority_queue<region*, vector<region*>, region_cmp> q;

        for(vector<region*>::iterator it = r1->v.begin(); it != r1->v.end(); ++it) {
                for(vector<region*>::iterator it2 = r2->v.begin(); it2 != r2->v.end(); ++it2) {
                        region *tmp = (*it)->intersect(*it2);
                        if (tmp != nullptr) {
                                tmp->nr_processed = 2;
                                q.push(tmp);
                        }
                }
        }      
        return q;
}

int main()
{
        scanf("%u %u %u\n", &n, &x, &y);

        vector<rect*> v;
        priority_queue<region*, vector<region*>, region_cmp> q;


        for(int i = 0; i < n; ++i) {
                unsigned int x1, y1, x2, y2;
                scanf("%u %u %u %u\n", &x1, &y1, &x2, &y2);
                rect *r = new rect( min(x1, x2), min(y1, y2), max(x1, x2), max(y1, y2) );
                //r->print();
                v.push_back(r);
        }
       
        if (n == 1) {
                for(vector<region*>::iterator it = v[0]->v.begin(); it != v[0]->v.end(); ++it) {
                        (*it)->nr_processed = 1;
                        q.push( *it );
                }
        } else {
                q = make_initial_q( v[0], v[1] );
        }
       
        while (!q.empty()) {
                region *r = q.top();
                region *rnew;

                if (r->nr_processed >= n) {
                        printf("%llu\n", r->area);
                        return 0;
                }
                q.pop();

                //r->print_area();
                //r->print();
                //printf("***\n");

                rnew = r->intersect( v[r->nr_processed]->v[0] );
                if (rnew != nullptr) {
                        rnew->nr_processed = r->nr_processed+1;
                        q.push(rnew);
                }
                rnew = r->intersect( v[r->nr_processed]->v[1] );
                if (rnew != nullptr) {
                        rnew->nr_processed = r->nr_processed+1;
                        q.push(rnew);
                }
                rnew = r->intersect( v[r->nr_processed]->v[2] );
                if (rnew != nullptr) {
                        rnew->nr_processed = r->nr_processed+1;
                        q.push(rnew);
                }
                rnew = r->intersect( v[r->nr_processed]->v[3] );
                if (rnew != nullptr) {
                        rnew->nr_processed = r->nr_processed+1;
                        q.push(rnew);
                }
                delete r;
        }

        return 0;
}