program yo;

var f,g:text;
    s:array[1..1000] of char;
    c:char;
    ss,m,k,o:integer;


begin
assign(f,'text.in'); reset(f);
assign(g,'text.out'); rewrite(g);
ss:=0;
while not eof(f) do
   begin
   o:=0;
   read(f,c);
   while ((c>='a') and (c<='z')) or ((c>='A') and (c<='Z')) do
       begin
       o:=o+1;
       s[o]:=c;
       read(f,c);
       end;
   if o<>0 then begin
                k:=k+1;
                ss:=ss+o;
                end;
   end;
m:=trunc(ss/k);
write(g,m);
close(f);
close(g);
end.