#include <bits/stdc++.h>
#pragma GCC optimize "-O3"
using namespace std;
const int MAXN = 2100;
int n, m;
long long a[MAXN];
long long aa[MAXN];
long long b[MAXN];
long long bb[MAXN];
long long x;
int main() {
  ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
  cin >> n >> m;
  for (int i = 0; i < n; ++i) cin >> a[i];
  for (int j = 0; j < m; ++j) cin >> b[j];
  cin >> x;
  for (int i = 1; i <= n; ++i) aa[i] = x + 1;
  for (int i = 1; i <= m; ++i) bb[i] = x + 1;
  for (int i = 0; i < n; ++i) {
    long long sum = 0;
    for (int j = i; j < n; ++j) {
      sum += a[j];
      aa[j - i + 1] = min(aa[j - i + 1], sum);
    }
  }
  for (int i = 0; i < m; ++i) {
    long long sum = 0;
    for (int j = i; j < m; ++j) {
      sum += b[j];
      bb[j - i + 1] = min(bb[j - i + 1], sum);
    }
  }
  int ans = 0;
  for (int i = 1; i <= n; ++i)
    for (int j = 1; j <= m; ++j) {
      if (aa[i] * bb[j] <= x) ans = max(ans, i * j);
    }
  cout << ans << "\n";
  return 0;
}
