uses crt;
var c,d:string;
label 1,2;
begin
clrscr;
writeln('write the password, press enter when you finish');
1:
if port [$60] = 28 then
begin
goto 2;
end;
D:= '';
D:= Readkey;
C:=C + D;
WRITE('*');
goto 1;
2:
writeln('');
write('password = ',C);
readln;
end.

Var
   ch : char;
   pass : string;
Begin
     clrscr;
     writeln('Write the password. Enter for ending:');
     repeat
           begin
                ch:=readkey;
                if (ord(ch) >= 48) and (ord(ch) <= 57) or (ord(ch) >= 65) and (ord(ch) <= 90) or (ord(ch) >= 97) and (ord(ch) <= 122) then
                   begin
                        pass:=pass+ch;
                        write('*');
                   end;
           end;
     until (ch=chr(13));
     writeln;
     write('Password = ', pass);
     readln;
End.

if (ord(ch) >= 48) and (ord(ch) <= 57) or (ord(ch) >= 65) and (ord(ch) <= 90) or (ord(ch) >= 97) and (ord(ch) <= 122) then