Program baitap;
Uses crt;
Var A:array[1..50] of integer;
    N,i:integer;
Begin
Clrscr;
Write('N='); Readln(N);
For i:=1 to N do
     Begin
     Write('A[',i,']=');
     Readln(A[i]);
     End;
For i:=1 to N do Write(A[i],' ');
Writeln('');
For i:=1 to N do If A[i] mod 2=0 then Write(A[i],' ');
Writeln(' ');
For i:=1 to N do If i mod 2=1 then Write(A[i],' ');
Readln
End.

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Đã test code

uses crt;
var a:array[1..1000]of longint; n,i:longint;
begin
 clrscr;
  readln(n);
  for i:=1 to n do readln(n);
  for i:=1 to n do if(i mod 2=1)then write(a[i],' ');
 readln
end.