Program Zadacha1;
Var N, i: Integer;
A: Array of Integer;
Begin
ReadLn(N);
If (N < 1) Or (N > 100) Then
WriteLn('Error!')
Else
Begin
SetLength(A, N);
For i := 0 To N - 1 Do
Begin
Read(A[i]);
If Abs(A[i]) > 10000 Then
Begin
WriteLn('Error!');
Break;
End;
End;
For i := 0 To N Do
If i Mod 2 = 0 Then
Write(A[i], ' ');
End;
ReadLn;
End.