program prob_text;
var f,g:text;
    x:char;
    n,l,t:longint;
    ok:0..1;
begin
assign(f,'text.in');
assign(g,'text.out');
reset(F);
rewrite(g);
n:=1;
l:=0;
while not eof(f) do
  begin
    read(f,x);
    ok:=0;
    if (ord(x)>96)and(ord(x)<123)then ok:=1 else
    if (ord(x)>64)and(ord(x)<91)then ok:=1;
    if (ok=1)then
      l:=l+1 else
      if (l>0)and(ok=0)then
        begin
          t:=t+l;
          n:=n+1;
          l:=0;
        end;
  end;
if (ok=0)then n:=n-1 else
  t:=t+l;
write(g,t div n);
close(f);
close(g);
end.