奇偶属性 Parity

标准数独基础上，每条线上的数字拥有相同的奇偶性。

Classic rules applied, additionally, numbers own same parity on same line.

◆我们可以使用O标记奇数，E标记偶数。

We can use O to mark it as odd (and E as even if necessary).

◆线上数字有时不能是某种奇偶性，否则某处会有过多的奇/偶数字。

Numbers on line cannot be one parity, otherwise somewhere will be too much odd/even.

◆确定的奇偶性 The certain parity

◆白格的奇偶属性 The parity in cells with no lines