ac1173.pas

某牛人写的acm.tongji.edu.cn上大部分ac的代码,仅供学习研究,请不要用来作弊

program tju1173;
const
  maxtree=262143;
var
  a:array[1..maxtree]of char;
  k:longint;
  c:char;
procedure cal(p,d:longint);
  begin
    if d=0 then
      if a[p]='0' then a[p]:='A' else a[p]:='B'
    else begin
      cal(p-d,d shr 1);
      cal(p+d,d shr 1);
      if a[p-d]=a[p+d] then a[p]:=a[p-d] else a[p]:='C';
    end;
  end;
procedure out(p,d:longint);
  begin
    write(a[p]);
    if a[p]='C' then begin
      out(p-d,d shr 1);
      out(p+d,d shr 1);
    end;
  end;
begin
  repeat
    k:=0;
    repeat
      inc(k);
      read(c);
      a[k*2-1]:=c;
    until seekeoln;
    readln;
    cal(k,k shr 1);
    out(k,k shr 1);
    writeln;
  until seekeof;
end.