// clang-format off
#define _CRT_SECURE_NO_WARNINGS

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cmath>
#include <stack>
#include <iomanip>
#include <fstream>
#include <string>
#include <set>
#include <deque>
#include <queue>
#include <map>
#include <bitset>
#include <random>
#include <list>
#include <unordered_map>
#include <unordered_set>
#include <cassert>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef string str;
//typedef __int128 ultraint;
#define sqrt sqrtl
#define F first
#define S second
#define endl '\n'
#define all(vc666) vc666.begin(), vc666.end()
#define allr(vc666) vc666.rbegin(), vc666.rend()
#define int long long

const ll INF = (ll)1e18 + 7;
const ll inf = 1e9 + 7;
const ll ONE = 1;
const ll MOD = (ONE << 32) - 1;
const ll max_sz = 1e7 + 1;
ld EPS = 1e-6;
ld PI = 3.1415926535897932384;
mt19937_64 gen(time(0));

struct Elem {
    int value, cnt;
};

bool cmp(const Elem& a, const Elem& b) {
    return a.value > b.value;
}

void solve() {
    int n, m, i, x, y, sup;
    cin >> n >> m;
    vector <int> elems(n);
    unordered_map <int, int> cnt;
    for (i = 0; i < n; i++) {
        cin >> elems[i];
        cnt[elems[i]]++;
    }
    sort(all(elems));
    elems.erase(unique(all(elems)), elems.end());
    unordered_map <int, int> idx;
    for (i = 0; i < (int)elems.size(); i++) {
        idx[elems[i]] = i;
    }
    vector <unordered_map <int, bool> > ban(elems.size());
    for (i = 0; i < m; i++) {
        cin >> x >> y;
        x = idx[x];
        y = idx[y];
        ban[x][y] = 1;
        ban[y][x] = 1;
    }
    vector <vector <Elem> > keys(n + 1);
    for (auto& it : cnt) {
        keys[it.second].push_back({ it.first, it.second });
    }
    vector <int> keys2;
    for (i = n; i > 0; i--) {
        if (keys[i].size() > 0) {
            sort(all(keys[i]), cmp);
            keys2.push_back(i);
        }
    }
    ll ans = 0;
    for (auto val : elems) {
        sup = cnt[val];
        // val - value
        // sup - cnt
        x = idx[val];
        for (auto& it : keys2) {
            for (auto& it2 : keys[it]) {
                if (val != it2.value && !ban[x][idx[it2.value]]) {
                    ans = max(ans, (ll)(sup + it2.cnt) * (ll)(val + it2.value));
                    break;
                }
            }
        }
    }
    cout << ans << endl;
}


signed main() {
#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    int t = 1;
    cin >> t;
    while (t--) {
        solve();
    }
}
//Deisgned by skimono