https://codeforces.com/contest/1974/problem/C

#include <bits/stdc++.h>
using namespace std;
#define int long long
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<VI> VVI;
#define rep(i,a,n) for (int i=a;i<=n;i++)
#define per(i,a,n) for (int i=a;i>=n;i--)
#define oz 998244353
#define N 200010
#define INF 0x3f3f3f3f
typedef long long ll;
#define endl '\n'
const int mod = 1e9 + 7;


void solve() {

    int n;
    cin >> n;
    vector<int> ar(n + 1);

    map<PII, int> a, b, c;
    map<vector<int>, int> d;

    for (int i = 1; i <= n; i++) {
        cin >> ar[i];
    }

    int res = 0;
    for (int i = 1; i <= n - 2; i++) {
        res += a[ {ar[i], ar[i + 1]}] ++;
        res += b[ {ar[i + 1], ar[i + 2]}] ++;
        res += c[ {ar[i], ar[i + 2]}] ++;

        vector<int> v = {ar[i], ar[i + 1], ar[i + 2]};

        res -=  d[v] * 3;
        d[v] ++;

    }

    cout << res << endl;
}

signed main() {

    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    int T = 1;
    cin >> T;
    while (T --)

        solve();

    return 0;
}