/* Problem URL: https://codeforces.com/problemset/problem/1986/F */ #include #include #include using namespace std; using namespace __gnu_pbds; template > using ordered_set = tree; #define V vector #define rmin(a, b) a = min(a, b) #define rmax(a, b) a = max(a, b) #define rep(i, lim) for (int i = 0; i < (lim); i++) #define nrep(i, s, lim) for (int i = s; i < (lim); i++) #define repv(i, v) for (auto &i : (v)) #define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; } #define sortv(v) sort(v.begin(), v.end()) #define all(v) (v).begin(), (v).end() using vi = vector; using vvi = vector; using vvvi = vector; using vvvvi = vector; using ll = long long; using vl = vector; using vvl = vector; using vvvl = vector; using vvvvl = vector; template auto operator<<(ostream &os, const vector &vec)->ostream& { os << vec[0]; for (size_t i = 1; i < vec.size(); i++) { os << ' ' << vec[i]; } os << '\n'; return os; } template auto operator>>(istream &is, vector &vec)->istream& { for (auto &i : vec) { is >> i; } return is; } template auto operator<<(ostream &os, const vector> &vec)->ostream& { for (auto &i : vec) { os << i[0]; for (size_t j = 1; j < i.size(); j++) { os << ' ' << i[j]; } os << '\n'; } return os; } template auto operator>>(istream &is, vector> &vec)->istream& { for (auto &i : vec) { for (auto &j : i) { is >> j; } } return is; } const int oo = INT32_MAX >> 1; const ll OO = INT64_MAX >> 1; void pre() { } #define TEST 1 void solve() { int n, m; cin >> n >> m; V>> graph(n); V rem(m); while (m--) { int a, b; cin >> a >> b; a--, b--; graph[a].emplace_back(b, m); graph[b].emplace_back(a, m); } V vis(n); vi t(n); vi mi(n); int tim = 0; int tt = 1; function dfs = [&](int i, int p) { vis[i] = true; t[i] = tim++; mi[i] = t[i]; for (auto [j, ind] : graph[i]) { if (j == p) { continue; } if (vis[j]) { rmin(mi[i], t[j]); continue; } rmin(mi[i], dfs(j, i)); if (mi[j] > t[i]) { rem[ind] = true; tt++; } } return mi[i]; }; dfs(0, 0); vl c(tt); vi g(n); vvi act(tt); int cur = 0; fill(all(vis), false); function func = [&](int i) { vis[i] = true; g[i] = cur; c[cur]++; for (auto [j, ind] : graph[i]) { if (vis[j] || rem[ind]) { continue; } func(j); } }; rep(i, n) { if (vis[i]) { continue; } func(i); cur++; } rep(i, n) { for (auto [j, ind] : graph[i]) { if (rem[ind]) { act[g[i]].push_back(g[j]); act[g[j]].push_back(g[i]); } } } repv(i, act) { sortv(i); i.erase(unique(all(i)), i.end()); } ll ans = (ll)n * (n - 1) / 2; function calc = [&](int i, int p) { ll count = c[i]; repv(j, act[i]) { if (j == p) { continue; } ll tm = calc(j, i); rmin(ans, tm * (tm - 1) / 2 + (n - tm) * (n - tm - 1) / 2); count += tm; } return count; }; calc(0, 0); cout << ans << '\n'; } int main() { ios::sync_with_stdio(false); cin.tie(nullptr); pre(); int t; (TEST && cin >> t) || (t = 1); while (t--) { solve(); } }