#include <bits/stdc++.h>

// https://codeforces.com/blog/entry/96344

#pragma GCC optimize("O2,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

using namespace std;

template <typename... Args>
void dbg(std::string const &str, Args &&...args) {
  std::cout << std::vformat(str, std::make_format_args(args...));
}

template <typename T>
void dbg(T const &t) {
  std::cout << t;
}

template <std::ranges::range T>
void dbgln(T const &t) {
  if constexpr (std::is_convertible_v<T, char const *>) {
    std::cout << t << '\n';
  } else {
    for (auto const &e : t) {
      std::cout << e << ' ';
    }
    std::cout << '\n';
  }
}

void dbgln() {
  std::cout << '\n';
}

template <typename... Args>
void dbgln(std::string const &str, Args &&...args) {
  dbg(str, std::forward<Args>(args)...);
  cout << '\n';
}

template <typename T>
void dbgln(T const &t) {
  dbg(t);
  cout << '\n';
}

template <typename T>
constexpr T MIN = std::numeric_limits<T>::min();

template <typename T>
constexpr T MAX = std::numeric_limits<T>::min();

template <typename T>
static T sc(auto &&x) {
  return static_cast<T>(x);
}

#define ff first
#define ss second
#define eb emplace_back
#define ll long long
#define ld long double
#define vec vector
#define endl '\n'

#define all(x) (x).begin(), (x).end()
#define rall(x) (r).rbegin(), (x).rend()
#define sz(x) static_cast<int>((x).size())
#define FOR(a, b, c) for (ll(a) = (b); (a) < (c); ++(a))
#define ROF(a, b, c) for (int(a) = (b); (a) > (c); --(a))

void solve() {
  ll x, y, z, k;
  cin >> x >> y >> z >> k;
  /*
     vol = k <= x * y * z

     explore all valid box volumes at 0, 0, 0

     a * b * c = k
     a * b = k / c <-> c = k / (a * b)
     a=1 -> b * c <= k - bsearch?
     */

  ll ans = 0;

  FOR(a, 1, x + 1) {
    FOR(b, 1, y + 1) {
      ll total = a * b;
      if (k % total == 0 && k / total <= z) {
        ans = max(ans, (x - a + 1) * (y - b + 1) * (z - k / total + 1));
      }
    }
  }

  dbgln(ans);
}

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);

  int t = 1;
  cin >> t;

  while (t--) {
    solve();
  }

  return 0;
}