> #include <iostream>
> #include <vector>
> using namespace std;
> 
> void main()
> {
>     int n;  cin >> n;
>     vector< vector<int> > homeworks(n, vector<int>(5));
>     for (int i=0;i<n;i++)
>     {
>         for (int j=0;j<4;j++)
>         {
>             cin >> homeworks[i][j];
>         }
>     }
>     for (i=0;i<n;i++)
>     {
>         if ( homeworks[i][3]-homeworks[i][2]==homeworks[i][2]-homeworks[i][1]==homeworks[i][1]-homeworks[i][0] )
>             homeworks[i][4] = homeworks[i][3]+homeworks[i][3]-homeworks[i][2];
>         else homeworks[i][4] = homeworks[i][3]/homeworks[i][2]*homeworks[i][3];
>     }
>     for (i=0;i<n;i++)
>     {
>         for (int j=0;j<5;j++)
>         {
>             cout << homeworks[i][j] << " ";
>         }
>         cout << endl;
>     }
> }
>