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#include<bits/stdc++.h> using namespace std; int n; long long a[2005]; int st[4 * 2005]; map<long long, vector<pair<int, int>>> mp; void update(int id, int l, int r, int i, int v){ if (i < l || i > r) return; if (l == r){ st[id] += v; if (v == 0) st[id] = 0; return; } int mid = (l + r) >> 1; update(2 * id, l, mid, i, v); update(2 * id + 1,mid + 1, r, i, v); st[id] = st[2 * id] + st[2 * id + 1]; } int get(int id, int l, int r, int u, int v){ if (u > v || r < u || l > v) return 0; if (l >= u && r <= v) return st[id]; int mid = (l + r) >> 1; return get(2 * id, l, mid, u, v) + get(2 * id + 1, mid + 1, r, u, v); } //7 //1 1 1 1 3 10 30 void solve(int testcase){ cin >> n; for (int i = 1; i <= n; i++) cin >> a[i]; sort(a + 1, a + 1 + n); mp.clear(); for (int i = 1; i <= n; i++){ for (int j = i + 1; j <= n; j++){ mp[a[i] * a[j]].push_back({i, j}); } } int ans = 0; for (map<long long, vector<pair<int, int>>>:: iterator it = mp.begin(); it != mp.end(); ++it){ vector<pair<int, int>> u = it -> second; int sz = u.size(); if (sz == 0) continue; sort(u.begin(), u.end()); for (int i = 1; i < sz; i++){ if (u[i].first != u[i - 1].first){ int p = i - 1; while(p >= 0 && u[p].first == u[i - 1].first) update(1, 1, n, u[p].second, 1), p--; } ans += get(1, 1, n, u[i].second + 1, n); } for (int i = 0; i < sz; i++) update(1, 1, n, u[i].second, 0); } cout << ans << '\n'; } int main(){ //freopen("input.txt", "r", stdin); int t = 1; cin >> t; for (int i = 1; i <= t; i++) solve(i); }
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