var f:text;
    cl,cc:longint;
    mid:longint;
    c:char;
const ALPHA = ['A'..'Z', 'a'..'z'];

begin
cl:=0;
cc:=0;
assign(f, 'text.in');
reset(f);
while EOF(f) = false do begin
read(f, c);
if c in ALPHA then
cl:=cl+1
else if c = ' '  then
cc:=cc+1;
end;
close(f);
assign(f, 'text.out');
rewrite(f);
cc:=cc+1;
mid:=Trunc(cl/cc);
write(f, mid);
close(f);
end.