POJ3974 (manacher)

var s,t:ansistring;
    n,op:longint;
    p:array[0..2000008] of longint;
procedure pre;
var i:longint;
begin
    s:='$*';
    for i:=1 to length(t) do
    begin
        s:=s+t[i]+'*';
    end;
    s:=s+'#';
    n:=length(s);
end;
function min(a,b:longint):longint;
begin
    if a<b then exit(a) else exit(b);
end;
procedure manacher;
var i,mx,id:longint;
begin
    fillchar(p,sizeof(p),0);
    mx:=0; id:=1; p[1]:=1;
    for i:=2 to n do
    begin
        p[i]:=1;
        if mx>i then p[i]:=min(mx-i,p[id*2-i]);
        while s[i+p[i]]=s[i-p[i]] do inc(p[i]);
        if p[i]+i>mx then begin mx:=p[i]+i; id:=i; end;    
    end;
end;    
procedure print;
var ans,i:longint;
begin
    //writeln(s);
    ans:=0;
    for i:=1 to n do if p[i]-1>ans then ans:=p[i]-1;
    writeln('Case ',op,': ',ans);
end;    
begin    
    op:=0;
    while true do
    begin
        inc(op);
        t:='';
        readln(t);
        if t='END' then break;
        pre;
        manacher;
        print;
    end;
end.