#include <bits/stdc++.h>
using namespace std;
long long fa[2005], fb[2005];
long long mina[2005], minb[2005];
signed main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int n, m;
  cin >> n >> m;
  vector<long long> a(n), b(m);
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    fa[i + 1] = fa[i] + a[i];
  }
  for (int j = 0; j < m; j++) {
    cin >> b[j];
    fb[j + 1] = fb[j] + b[j];
  }
  long long x;
  cin >> x;
  for (int i = 0; i <= n; i++) {
    mina[i] = 2000000000;
    for (int k = 0; k + i <= n; k++) {
      mina[i] = min(mina[i], fa[k + i] - fa[k]);
    }
  }
  for (int j = 0; j <= m; j++) {
    minb[j] = 2000000000;
    for (int k = 0; k + j <= m; k++) {
      minb[j] = min(minb[j], fb[k + j] - fb[k]);
    }
  }
  long long ans = 0;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      if (mina[i] * minb[j] <= x) ans = max(ans, i * 1ll * j);
    }
  }
  cout << ans;
}
