uses
    crt;
var
    x:word;

function DecToBin(const y:word) : string;
var
    x:word;
    str1,str2:string[16];
begin
    x:=y;
    str1:='';
    if x=0 then DecToBin:='0';
    while (x<>0) do
      begin
        str(x mod 2, str2);
        str1:=str2+str1;
        x := x div 2;
      end;
    DecToBin:=str1;
end;

begin
    clrscr;

    write('vvedite x = ');
    readln(x);

    writeln(DecToBin(x));

    readkey;
end.