const m:set of char=['a'..'z','A'..'Z'];
var ct,S,d:longint;
    c1:char;
    f:text;
begin
assign(f,'text.in'); reset(f);
d:=0;
ct:=0;
s:=0;
while (not eof(f)) do
 begin
   read(f,c1);
   if c1 in m
     then
      begin
        d:=d+1;
        inc(S);
      end;
   if (([c1]*m=[]) and (d<>0))
      then
        begin
          inc(ct);
          d:=0;
        end;
 end;
close(f);
assign(f,'text.out'); rewrite(f);
if ct=0 then writeln(f,'0')
  else writeln(f,S div ct);
close(f);
end.