program Zadacha;

{$APPTYPE CONSOLE}

uses
  SysUtils;
 var i,m,n:integer;
 c:char;
 A:array[0..9] of byte;
 f1,f2:text;
begin
  { TODO -oUser -cConsole Main : Insert code here }
 assign(f1,'count.in');
 assign(f2,'count.out');
 reset(f1);
 rewrite(f2);
 while not eoln(f1) do
 begin
  read(f1,c);
  val(c,m,i);
  A[m]:=1;
 end;
 n:=0;
 for i:=0 to 9 do
 begin
  if (A[i]=1) then inc(n);
 end;
 writeln(f2,n);
 close(f1);
 close(f2);
end.