#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N=(int)500000;
const LL INF=(LL)1e18;
int p[N+2][2],r[N+2][2];
int n,m,d;
namespace problem1{
bool check(){
return n+m<=5000;
}
LL form_swap(int x,int a,int y){
if (a>y) return -1;
if (a<x && a+d>y) return -1;
if (x<=a && a<=y) return a;
return a+d;
}
LL Cost(int x,int y){
vector<int>v;
for(int i=1;i<=n;++i){
if (form_swap(x,p[i][0],y)==-1) return INF;
v.push_back(r[i][0]);
// cout<<form_swap(x,p[i][0],y)<<' '<<x<<' '<<y<<'\n';
}
for(int i=1;i<=m;++i){
if (form_swap(x,p[i][1],y)==-1) v.push_back(r[i][1]);
}
sort(v.begin(),v.end()); v.resize(unique(v.begin(),v.end())-v.begin());
int height=y-x+1;
int weight=v.back()-v.front()+1;
v.push_back(v[0]);
for(int i=1;i<v.size()-1;++i){
weight=min(weight,v[i-1]+d-v[i]+1);
}
return (LL)height*weight;
}
void main_code(){
LL ans=INF;
for(int x=0;x<=d;++x){
for(int y=x;y<=2*d;++y){
ans=min(ans,Cost(x,y));
}
}
cout<<ans<<'\n';
}
}
int main(){
ios::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
// freopen("txt.inp","r",stdin);
// freopen("txt.out","w",stdout);
cin>>n>>m>>d;
for(int i=1;i<=n;++i) cin>>p[i][0]>>r[i][0];
for(int i=1;i<=m;++i) cin>>p[i][1]>>r[i][1];
if (problem1::check()) return problem1::main_code(),0;
}
