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#include <bits/stdc++.h>
using namespace std;
#define FOR(i,x,y) for(int i=(int)(x);i<(int)(y);++i)
#define FORE(i,x,y) for(int i=(int)(x);i<=(int)(y);++i)
#define FORD(i,x,y) for(int i=(int)(x);i>=(int)(y);--i)
#define PB push_back
#define MP make_pair
#define ST first
#define ND second
typedef long long ll;
typedef pair<int,int> pii;
const int MAXN=5e5+6;
const int INF=1e9+1000;

int n,X,Y;
int ansa=0,ansb=0;
pii a[MAXN];
pii b[MAXN];
int sa,sb;
int mia=INF,mib=INF;
int mxa=-1,mxb=-1;
int resa[MAXN];
int resb[MAXN];
pii ca[MAXN];
pii cb[MAXN];
int main()
{
    ios_base::sync_with_stdio(false);cin.tie(0);
    cin>>n>>X>>Y;
    FOR(i,0,n){
        cin>>a[i].ST>>b[i].ST>>a[i].ND>>b[i].ND;
        /*if(a[i].ST==0)a[i].ST=X;
        if(a[i].ND==0)a[i].ND=Y;
        if(b[i].ST==0)b[i].ST=X;
        if(b[i].ND==0)b[i].ND=Y;*/
        if(a[i].ST>a[i].ND)swap(a[i].ST,a[i].ND);
        if(b[i].ST>b[i].ND)swap(b[i].ST,b[i].ND);

        mia=min(mia,a[i].ST);
        mxa=max(mxa,a[i].ND);
        mib=min(mib,b[i].ST);
        mxb=max(mxb,b[i].ND);
        ca[i]=a[i];
        cb[i]=b[i];
    }
    sort(a,a+n);
    sort(b,b+n);
    sort(ca,ca+n);
    sort(cb,cb+n);
    int na=0;
    int nb=0;
    FOR(i,1,n){
        if(ca[i].ND>ca[na].ND){
            ca[++na]=ca[i];
            if(ca[na-1].ND>ca[na].ST){
                ca[na-1].ND=ca[na].ND;
                --na;
            }
        }
    }
    ++na;
    FOR(i,1,n){
        if(cb[i].ND>cb[nb].ND){
            cb[++nb]=cb[i];
            if(cb[nb-1].ND>cb[nb].ST){
                cb[nb-1].ND=cb[nb].ND;
                --nb;
            }
        }
    }
    ++nb;
    sa=mia+X-mxa;
    sb=mib+Y-mxb;
    int mxL=a[0].ST;
    multiset<int> lp;
    multiset<int,greater<int> > pp;
    multiset<int,greater<int> >::iterator it;
    priority_queue<int,vector<int>,greater<int> > zk;
    priority_queue<int,vector<int>,greater<int> > ptm;
    FOR(i,0,n){
        if(mxL<a[i].ST)sa+=a[i].ST-mxL;
        mxL=max(mxL,a[i].ND);
        lp.insert(a[i].ST);
        pp.insert(a[i].ND);
    }
    int j=0;
    FOR(i,0,n){
        lp.erase(lp.find(a[i].ST));
        pp.erase(pp.find(a[i].ND));

        while(j<n&&a[j].ST==a[i].ST)zk.push(a[j].ND),++j;
        while(zk.size()>0&&zk.top()<=a[i].ST)zk.pop();
        if(lp.empty()){
            ansa=max(ansa,zk.top()-a[i].ST);
        }else{
            int posp=lower_bound(ca,ca+na,a[i])-ca;
            posp=ca[posp].ND;
            it=pp.lower_bound(posp);
            if(it==pp.end()){
                ansa=max(ansa,min(*lp.begin(),zk.top())-a[i].ST);
            }else{
                ansa=max(ansa,min(a[i].ND-a[i].ST,max(0,min(*lp.begin(),zk.top())-a[i].ST)+max(0,min(a[i].ND,zk.top())-*it)));
                ansa=max(ansa,min(*lp.begin(),zk.top())-a[i].ST);
            }
        }

        ptm.push(a[i].ND);
        while(ptm.size()>0&&(i+1>=n||ptm.top()<a[i+1].ST)){
            while(zk.size()>0&&zk.top()<=ptm.top())zk.pop();
            int x=INF;
            if(!lp.empty())x=min(x,*lp.begin());
            if(!zk.empty())x=min(x,zk.top());
            if(i+1<n)x=min(x,a[i+1].ST);
            if(x==INF)x=-1;
            ansa=max(ansa,x-ptm.top());
            ptm.pop();
        }


    }
    mxL=b[0].ST;
    lp.clear();
    pp.clear();
    while(!zk.empty())zk.pop();
    while(!ptm.empty())ptm.pop();
    FOR(i,0,n){
        if(mxL<b[i].ST)sb+=b[i].ST-mxL;
        mxL=max(mxL,b[i].ND);
        lp.insert(b[i].ST);
        pp.insert(b[i].ND);
    }
    j=0;
    FOR(i,0,n){
        lp.erase(lp.find(b[i].ST));
        pp.erase(pp.find(b[i].ND));

        while(j<n&&b[j].ST==b[i].ST)zk.push(b[j].ND),++j;
        while(zk.size()>0&&zk.top()<=b[i].ST)zk.pop();
        if(lp.empty()){
            ansb=max(ansb,zk.top()-b[i].ST);
        }else{
            int posp=lower_bound(cb,cb+nb,b[i])-cb;
            posp=cb[posp].ND;
            it=pp.lower_bound(posp);
            if(it==pp.end()){
                ansb=max(ansb,min(*lp.begin(),zk.top())-b[i].ST);
            }else{
                ansb=max(ansb,min(b[i].ND-b[i].ST,max(0,min(*lp.begin(),zk.top())-b[i].ST)+max(0,min(b[i].ND,zk.top())-*it)));
                ansb=max(ansb,min(*lp.begin(),zk.top())-b[i].ST);
            }


        }

        ptm.push(b[i].ND);
        while(ptm.size()>0&&(i+1>=n||ptm.top()<b[i+1].ST)){
            while(zk.size()>0&&zk.top()<=ptm.top())zk.pop();
            int x=INF;
            if(!lp.empty())x=min(x,*lp.begin());
            if(!zk.empty())x=min(x,zk.top());
            if(i+1<n)x=min(x,b[i+1].ST);
            if(x==INF)x=-1;
            ansb=max(ansb,x-ptm.top());
            ptm.pop();
        }


    }
    cout<<(ll)max(ansa,sa)*(ll)max(ansb,sb)<<"\n";
    return 0;
}