program litere;
uses crt;
var a:char;
    nrl,i:longint;
    nrc:word;
    f,g:text;
    o:boolean;
begin
     assign(f,'text.in');
     assign(g,'text.out');
     reset(f);
     rewrite(g);
     nrc:=0;
     nrl:=0;
     o:=false;
     repeat
           repeat
           read(f,a);
           if (a in ['A'..'Z'])or(a in['a'..'z'])then
              begin
                   nrl:=nrl+1;
                   o:=true;
              end
           else
           begin
if (o)and((a in['~','!','{','@','#','$','%','^','&','(',')','-','}',' '])or(a in ['0'..'9'])) then
                 begin
                      nrc:=nrc+1;
                      o:=false;
                 end;
if (o)and(a in['|','"',':','+','?','=','<','>','.',',','/',';','[',']','\'])then
      begin
                      nrc:=nrc+1;
                      o:=false;
                 end;
                 end;
           until eoln(f);
           readln(f);
     until eof(f);
    writeln(g,nrl div (nrc+1));
    close(f);
    close(g);
end.