program text;

var s:ansistring;
    l,c:int64;
    gasit:boolean;

procedure afisare;
var i:longint;
    e:double;
begin
assign(output,'text.out');
rewrite(output);
if c<>0 then
   i:=l div c
   else i:=0;
write(i);
close(output);
end;

procedure procesare;
var i:longint;
begin
for i:=1 to length(s) do
    if (s[i] in ['A'..'Z','a'..'z']) then
       l:=l+1
       else if (l>=1) and (s[i-1] in ['A'..'Z','a'..'z']) and
               not (s[i] in ['A'..'Z','a'..'z']) then
               inc(c);
//if s[length(s)]in ['A'..'Z','a'..'z']
//   then begin c:=c+1; gasit:=true end
end;

procedure citire;
begin
assign(input,'text.in');
reset(input);
l:=0;
c:=0;
gasit:=false;
while not seekeof do
      begin
      readln(s);
      s:=s+'.';
      procesare;
      s:='';
      end;

afisare;
close(input);
end;

begin
citire;
end.