Maximum_Trio.cpp

#include <bits/stdc++.h>
#define fast_io ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
using namespace std;
#define ll long long
#define ull unsigned long long
#define readi(x) int x; cin >> x
#define readll(x) ll x; cin >> x
#define reads(s) string s; cin >> s
#define rep(a, b) for (ll i = a; i < b; ++i)
#define repi(i, a, b) for (ll i = a; i < b; ++i)
#define repd(i, a, b) for (ll i = a; i > b; --i)
#define all(x) (x).begin(), (x).end()
#define init_arr readll(n); vll arr(n); rep(0, n) cin >> arr[i];
#define vprint(i) for (auto &j : i) cout << j << ' '; nl
#define mpprint(mp) for (auto &i : mp) { cout << i.ff << ' ' << i.ss << '\n'; }
#define vvprint(arr) for (auto &i : arr) { vprint(i) }
#define vvcin(n, m, arr) repi(i, 0, n) repi(j, 0, m) cin >> arr[i][j];
#define vcin(n, arr) rep(0, n) cin >> arr[i];
#define umcll unordered_map<char, ll >
#define umsll unordered_map<string, ll >
#define umll unordered_map<ll, ll >
#define print(num) cout << num << '\n';
#define mpcll map<char, ll >
#define mpsll map<string, ll >
#define mpll map<ll, ll >
#define nl cout << '\n';
#define inf (1LL << 60)
#define vll vector<ll >
#define vi vector<int >
#define vii vector<vi >
#define vs vector<string >
#define vss vector<vs >
#define vb vector<bool >
#define pb push_back
#define pii pair<int, int>
#define pll pair<ll, ll>
#define mod 1e9 + 7
#define ff first
#define ss second
#define N 1e6

ll solve(vll arr) {
	ll n = arr.size();
	ll mx = LONG_MIN, mx2 = LONG_MIN, mn = LONG_MAX;
	// rep(0, n)
	// {
	// 	mn = min(mn, arr[i]);
	// 	if (arr[i] > mx)
	// 	{
	// 		mx = arr[i];
	// 	}
	// 	else
	// 	{
	// 		mx2 = max(mx2, arr[i]);
	// 	}
	// }
	sort(arr.begin(), arr.end());
	mx = arr[n - 1], mx2 = arr[n - 2], mn = arr[0];
	return (mx - mn) * mx2;
}

int main() {
	fast_io;
	ll t = 1;
	cin >> t;
	while (t--) {
		readll(n);
		vll arr(n);
		vcin(n, arr);
		cout << solve(arr) << '\n';
	}
	return 0;
}