差1 Difference 1

标准数独基础上，每个线索和真实的数字之间相差是1。

Classic rules applied. Additionally, each clue has 1 difference with the true number.

我们可以将它转化为候选数数独去解决。提示0意味着真实的数字是1，提示1意味着2，提示3意味着2或4。

We can change it into Candidates to solve. Clue 0 means the ture number is 1, clue 1 means 2, clue 3 means 2 or 4.

此外，提示一定与真实的数字有着相反的奇偶性。

And also, the clue has opposite parity with the true number.