For a real number \(x\), evaluate \((1+\sqrt{x})/(x-3)\) when it is defined.

Input

One real number \(x\).

Output

Start the output with Nhap x =. If \(x<0\) or \(x=3\), append Bieu thuc khong xac dinh. Otherwise append Ket qua: followed by the value, formatted with at most six significant digits and no unnecessary trailing zeros.

Example

Input

4

Output

Nhap x = Ket qua: 3