program z1354;

{$APPTYPE CONSOLE}

var mas:array [0..50000] of integer;
    n,i,j,max:integer;
    s:string;
    ch:char;
begin
 s:='';
 while not eof do
  begin
    read(ch);
    if ch in ['a'..'z','A'..'Z'] then
     s:=s+ch;
  end;
 n:=length(s);
 max:=0;
 for i:=1 to n do
  begin
    for j:=n downto i+1 do
      if s[j]=s[n-i+1] then mas[j]:=mas[j-1]+1 else mas[j]:=0;
    if mas[n]>max then max:=mas[n];
  end;
 for i:=1 to n do write(s[i]);
 for i:=n-max downto 1 do write(s[i]);

end.

Have no idea why this happened, but I've got WA 31 with Z-function and instant AC with prefix-function afterwards. O_o Can we somehow get the test 31?

Edited by author 04.12.2013 04:59