type Multime = set of char;
var m:multime;
    c:char;
    f,g:text;
    c1,k,cuv:integer;
begin
assign(f,'text.in');
reset(f);
m:=['a'..'z']+['A'..'Z'];
c1:=0;
k:=0;
cuv:=0;
while not eof(f) do
  begin
  read(f,c);
if c in m then
 begin
 inc(c1);
 if k=0 then
    begin
    cuv:=cuv+1;
    k:=1;
    end;
end
else
    k:=0;
end;
Close(f);
assign(g,'text.out');
rewrite(g);
writeln(g,c1 div cuv);
Close(g);
end.