#include <bits/stdc++.h>
using namespace std;
int ceil(int a, int b)
{
return (a + b - 1) / b;
}
int cnt(int st, int d, int x) // cate numere dau restul x la impartire prin d pana in st
{
if (st < x)
{
return 0;
}
return (st - x) / d + 1;
}
bool in_range(int st, int dr, int d, int x)
{
return cnt(dr, d, x) - cnt(st - 1, d, x);
}
int get_min(vector<int> resturi, int d) // lungime minima care acopera resturile
{
sort(resturi.begin(), resturi.end());
int ans = resturi.back() - resturi.front() + 1;
for (int i = 1; i < (int)resturi.size(); ++i)
{
ans = min(ans, d - (resturi[i] - resturi[i - 1] - 1));
}
return ans;
}
int32_t main()
{
cin.tie(nullptr)->sync_with_stdio(false);
int d, n, m;
cin >> n >> m >> d;
vector<pair<int, int>> si(n + 1);
vector<pair<int, int>> sau(m + 1);
for (int i = 1; i <= n; ++i)
{
cin >> si[i].first >> si[i].second;
}
for (int i = 1; i <= m; ++i)
{
cin >> sau[i].first >> sau[i].second;
}
int ans = INT_MAX;
for (int i = 0; i < d; ++i)
{
for (int j = i; j < i + d; ++j)
{
bool ok = true;
for (int k = 1; k <= n; ++k)
{
if (!in_range(i, j, d, si[k].first))
{
ok = false;
break;
}
}
if (!ok)
continue;
vector<int> resturi;
for (int k = 1; k <= n; ++k)
{
resturi.push_back(si[k].second);
}
for (int k = 1; k <= m; ++k)
{
if (in_range(i, j, d, sau[k].first))
{
continue;
}
resturi.push_back(sau[k].second);
}
ans = min(ans, (j - i + 1) * get_min(resturi, d));
}
}
cout << ans;
}
