#include <bits/stdc++.h>

using namespace std;

using ll = long long;

void solve()
{
    int n;
    cin>>n;
    int temp;
    ll Sum = 0;
    ll Xor = 0;
    for (int i = 0; i<n; i++)
    {
        cin>>temp;
        Sum+=temp;
        Xor^=temp;
    }
    vector<ll> answer;
    ll good = (1ll<<50) + Sum%2;
    Sum+=good;
    Xor^=good;
    ll need = 2*Xor - Sum;
    cout<<3<<endl<<good<<' '<<need/2<<' '<<need/2<<endl;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(nullptr);

    int t;
    cin>>t;
    for (int i = 0; i<t; i++) solve();

}