P132SUMJ_HoanViChuSo

const fi='P132SUMJ.inp';
      fo='P132SUMJ.out';

var s, ss, ans, tmp: string;
    n, i, l: longint;
    f: array [1..6] of boolean;
    find: boolean;

procedure thu;
var i: longint;
begin
  if l=n then
    begin
      if ans>ss then
        begin
          writeln(ans);
          find:=true;
        end;
    end
  else
    begin
      for i:=1 to n do
        if not f[i] then
          begin
            inc(l); ans[l]:=ss[i]; f[i]:=true;
            thu;
            if find then exit;
            f[i]:=false; dec(l);
          end;
    end;
end;

procedure Sort(l, r: longint);
var i, j: longint;
    m, tmp: char;
begin
  if l>=r then exit;
  i:=l; j:=r; m:=ss[(l+r) div 2];
  while i<=j do
    begin
      while ss[i]<m do inc(i);
      while ss[j]>m do dec(j);
      if i<=j then
        begin
          tmp:=ss[i]; ss[i]:=ss[j]; ss[j]:=tmp;
          inc(i); dec(j);
        end;
    end;
  Sort(l, j); Sort(i, r);
end;

begin
  assign(input, fi); reset(input);
  assign(output, fo); rewrite(output);

  readln(s);
  n:=length(s); ss:=s; ans:=s;
  tmp:=''; for i:=n downto 1 do tmp:=tmp+s[i];
  sort(1, n);

  if tmp=s then writeln(0) else
  begin
    fillchar(f, sizeof(f), false); l:=0;
    thu;
    if not find then writeln(0);
  end;

  close(input); close(output);
end.