program count;
var N,rez,a,b : integer;
    f,f1 : text;

begin
assign (f, 'count.in');
reset (f);
read (f,N);
close (f);

begin
if N mod 10<10 then
if N mod 10>1 then
a:=1;
end;

begin
if N mod 100<100 then
if N mod 100>10 then
a:=2;
end;

begin
if N mod 1000<1000 then
if N mod 1000>100 then
a:=3;
end;






assign (f1,'count.out');
rewrite (f1);
write (f1,a);
close (f1);
end.