```pascal
program KiemTraXepVienBi;

var
n, i, count: integer;

begin
writeln('Nhap so luong vien bi (n): ');
readln(n);

i := 1;
count := 0;

while count < n do
begin
count := count + i;
i := i + 1;
end;

if count = n then
writeln('Co the xep ', n, ' vien bi theo yeu cau.')
else
writeln('Khong the xep ', n, ' vien bi theo yeu cau.');
end.
```