program z1226;
uses crt;
var n:longint;
m:set of 0..9;
k:byte;
BEGIN
writeln('vvesti chislo');
readln(n);
m:=[ ];
k:=0;
while n<>0 do
begin if not ((n mod 10)in m) then
begin m :=m+[n mod 10];
inc (k);end;
n:=n div 10;end;
writeln(k);
readln;
END.