here is my program

var a,b:array[1..100000] of longint;
    i,k,l,n,m:longint;
    f1,f2:text;
    s:string;
begin
    readln(n);
    for i:=1 to n do
      readln(a[i]);
    readln(s);
    readln(m);
    for k:=1 to m do
      readln(b[k]);
    for k:=1 to n do
      for i:=2 to n do
        if a[i]<a[i-1] then begin l:=a[i]; a[i]:=a[i-1]; a[i-1]:=l; end;
    for i:=1 to m do
    writeln(a[b[i]]);
    readln;
end.

You should use fast sort
buble sort too long

qsort fast enough

use hash, no necessary to sort actually.