const Nmax=1000000000;
var N,c,b,i,f,s,j:integer;
k:array[1..Nmax] of integer;
input,output:text;
begin
assign (input,'count.in');
reset (input);
readln(input,N);
C:=1;
while (N>0) do
B:=N mod 10;
N:=N div 10;
S:=S+1;
 begin
for I:=1 to S do
 K[i]:=N mod 10;
 N:=N div 10;
  end;
  for i:=2 to S do
   for J:=1 to S do
  if K[j]<>K[i] then C:=C+1;
  i:=i+1;
assign (output,'count.out');
rewrite(output);
write(output,c);
close(input);
close(output);
end.