func_code_string: #include <bits/stdc++.h>   using namespace std;   long long M = 1e9 + 7;   void solve() {     long long int n;     cin >> n;     vector<long long int> a(n);     long long int sum = 0;     long long int x = 0;     for (long long int i = 0; i < n; i++) {       cin >> a[i];       sum += a[i];       x = x ^ a[i];     }     cout << 2 <<   n ;     cout << x <<     << sum + x <<   n ;   }   signed main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     ;     long long int t;     cin >> t;     while (t--) {       solve();     }   }   