Code : Absolute Zero

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

#define int long long

void solve(vector<int> &a) {
    int n = a.size();
    vector<int> seq;

    for (int i = 0; i < 39; i++) {
        int mx = *max_element(a.begin(), a.end());
        int mid = (0 + mx) / 2;
        for (auto &ele : a) {
            ele = abs(ele - mid);
        }
        seq.push_back(mid);
    }

    int remain = a.front();
    seq.push_back(remain);
    for (auto &ele : a) {
        ele = abs(ele - remain);
    }

    if (*max_element(a.begin(), a.end()) == 0) {
        cout << 40 << "\n";
        for (auto &ele : seq) {
            cout << ele << " ";
        }
        cout << "\n";
    } else {
        cout << "-1"
             << "\n";
    }
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int t;
    cin >> t;
    for (int zz = 0; zz < t; zz++) {
        int n;
        cin >> n;
        vector<int> a(n);
        for (int i = 0; i < n; i++) {
            cin >> a[i];
        }
        solve(a);
    }
}