var k,c:longint;
    m:set of 'a'..'z';
    n:set of 'A'..'Z';
    f,g:text;
    p:boolean;
    ch:char;
begin
assign(f,'text.in');
assign(g,'text.out');
reset(f);
rewrite(g);
c:=0;
k:=0;
m:=['a'..'z'];
n:=['A'..'Z'];
p:=false;
while not seekeof(f) do begin
while not seekeoln(f) do
      begin
      read(f,ch);
      if ch in m+n then begin
                        inc(k);
                        p:=false;
                        end
                   else if (k>0) and (not p) then begin
                                                  inc(c);
                                                  p:=true;
                                                  end;
      end;
      if ch in m+n then begin
                        inc(c);
                        p:=true;
                        end;
      readln(f);
      end;
write(g,k div c);
close(f);
close(g);
end.