排除 Elimination

标准数独基础上，圆圈内提示不能出现在圆圈周围。

Classic rules applied, numbers in circle cannot be around to the circle.

练习 Practice

① 找到例1中的所有的1 Find all 1 in Practice-1.

② 解答例2中的问号格 Find out the ？cell in Practice-2.

Practice 1 and 2

③ 例3的下一步是？它是一个合格的谜题吗？

What is the next step in Practice-3? Is this puzzle a right puzzle?

答案 Answer

① A1, B4, C3, F2, E6, D5; ② C1=6. ③ C2=4; No.