#include <bits/stdc++.h>
using namespace std;
long long n, m, x, a[3000], b[3000], qmi[3000], ymi[3000];
string s;
int main() {
  iostream::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  cin >> n >> m;
  for (int i = 0; i < n; i++) {
    cin >> a[i + 1];
    a[i + 1] += a[i];
  }
  for (int j = 0; j < m; j++) {
    cin >> b[j + 1];
    b[j + 1] += b[j];
  }
  cin >> x;
  for (int l = 1; l <= n; l++) {
    qmi[l] = x + 1;
    for (int j = 0; j + l <= n; j++) {
      qmi[l] = min(qmi[l], a[j + l] - a[j]);
    }
  }
  for (int l = 1; l <= m; l++) {
    ymi[l] = x + 1;
    for (int j = 0; j + l <= m; j++) {
      ymi[l] = min(ymi[l], b[j + l] - b[j]);
    }
  }
  int ans = 0;
  for (int l = 1; l <= n; l++) {
    for (int xl = 1; xl <= m; xl++) {
      if (qmi[l] <= x / ymi[xl]) {
        ans = max(ans, l * xl);
      }
    }
  }
  cout << ans << "\n";
  return 0;
}
