Program Mengurutkan Angka dari Kecil ke Besar

uses crt;
var
a,b,c: integer;
u:char;
label x;
begin
clrscr;
x:
        write('Masukkan bilangan pertama: ');
        readln(a);
        write('Masukkan bilangan kedua: ');
        readln(b);
        write('Masukkan bilangan ketiga: ');
        readln(c);
        if (a<b) and (a<c) and (b<c) then writeln (a,' ',b,' ',c)
        else if (a<b) and (a<c) and (c<b) then writeln(a,' ',c,' ',b)
        else if (b<a) and (b<c) and (a<c) then writeln(b,' ',a,' ',c)
        else if (b<a) and (b<c) and (c<a)  then writeln(b,' ',c,' ',a)
        else if (c<a) and (c<b) and (a<b) then writeln(c,' ',a,' ',b)
        else if (c<a) and (c<b) and (b<a) then writeln(c,' ',b,' ',a)
        else writeln('error');

        write('Ulangi {y/n} : '); readln(u);
        if u='y' then goto x;

        readln;
end.