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#include <bits/stdc++.h>
using namespace std;
int n;
void solve() {
    cin>>n;
    if(n==2){
        cout<<"1 -3 -3 1";
        return;
    }
    if(n==3){
        cout<<"1 -10 6 6 -10 1";
        return;
    }
    cout<<1<<' ';
    for(int i=1;i<=(n*2-1)/2;i++){
     cout<<"2 -1 ";
    }
    cout<<3-n;
}


signed main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int T;
    cin>>T;
    while(T--){
        solve();
    cout<<"\n";
}
    return 0;
}

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#include <bits/stdc++.h>
using namespace std;

bool ask(int u, int v) {
    bool res = 0;
    cout << "? " << u << " " << v << endl;
    cin >> res;
    return res;
}

void answer(int u) { cout << "! " << u << endl; }

void solve() {
    int n;
    cin >> n;
    vector<pair<int, int>> vec;
    vector<int> vis(n + 1);
    for (int i = 1; i + 1 <= n; i += 2) {
        if (ask(i, i + 1)) {
            vec.emplace_back(i, i + 1);
            vis[i] = vis[i + 1] = 1;
        }
    }
    if (vec.size() > 1) {
        answer(1);
        return;
    }
    if (n % 2) {
        int u = 1;
        while (vis[u])
            u++;
        if (ask(n, u)) {
            vec.emplace_back(n, u);
            vis[n] = vis[u] = 1;
        }
    }
    if (vec.size() != 1) {
        answer(1);
        return;
    }
    auto [u, v] = vec.front();
    int p = 1;
    while ((p == u or p == v) and p <= n)
        p++;
    int q = 1;
    while ((q == p or q == u or q == v) and q <= n)
        q++;
    bool res1 = ask(u, p);
    bool res2 = ask(v, p);
    bool res3;
    if (res1 == 0 and res2 == 0) {
        answer(1);
        return;
    }
    if (res1) {
        res3 = ask(u, q);
    }
    if (res2) {
        res3 = ask(v, q);
    }
    if (res3)
        answer(2);
    else
        answer(1);
    return;
}

signed main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int T = 1;
    cin >> T;
    while (T--)
        solve();
    return 0;
}

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#include <bits/stdc++.h>
using namespace std;

#define int long long
void solve() {
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    auto mit = min_element(a.begin(), a.end());
    auto sumlft = accumulate(a.begin(), mit, 0ll);
    auto sumrht = accumulate(next(mit), a.end(), 0ll);
    double ans = -1;
    if (1.0 * sumlft / (mit - a.begin()) - 1.0 * sumrht / (a.end() - next(mit)) > 1e-5) {
        sumlft += *mit;
        for (auto it = next(mit); it != a.end(); it++) {
            sumlft += *it;
            ans = max(ans, 1.0 * sumlft / (it - a.begin() + 1));
        }
    } else {
        sumrht += *mit;
        for (auto it = prev(mit); it - a.begin() >= 0; it--) {
            sumrht += *it;
            ans = max(ans, 1.0 * sumrht / (a.end() - it));
        }
    }
    cout << fixed << setprecision(20) << ans << "\n";
}

signed main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int T = 1;
    cin >> T;
    while (T--)
        solve();
    return 0;
}