func_code_string: #include<bits/stdc++.h>   using namespace std;   #include<algorithm>   #include<map>   #include<fstream>   #define ll long long   #define ld long double   #define pb push_back   #define fi first   #define se second   #define endl   n    #define For(i,n) for(long long i=0; i<n; i++)   #define FOR(i,f,l) for(long long i=f; i<l; i++)   #define fastio ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);   #define mod 1000000007      void solve(){     ll n;     cin>>n;     vector<ll> v(n),ans;     For(i,n){       cin>>v[i];     }     if(n==1){       cout<<0<<endl;     }     else{       ans.pb(0);       for(ll i=1; i<n; i++){           if((v[i]&v[i-1])==v[i-1]){               ans.pb(0);           }           else{               ll temp = v[i]^v[i-1];               temp = temp&v[i-1];             //  cout<<i<<endl;              // cout<<temp<<   <<1<<endl;               ans.pb(temp);               v[i] = v[i]+temp;             //  cout<<v[i]<<   <<2<<endl;           }       }       for(ll i=0; i<n; i++){           cout<<ans[i]<<   ;       }       cout<<endl;     }      }         int main(){      fastio      ll t;      cin>>t;      while(t--){        solve();      }   }      