规则Rules：

标准数独基础上，圈内数字为A，则其周围有A个质数。符合条件的A均已标出。

Classic rules applied. Additionally, if the circle contains A, there are A prime numbers around it. All the cases fit the rules are marked.

[注释1]周围Around：

*指与目标单元格通过边和角相邻的所有单元格（最多八个），不包括目标单元格自身。All the cells sharing an edge or a corner with the goal cell (no more than eight cells). And doesn't conclude about the goal itself.

[注释2]质数Prime：

*指约数仅有自身和1的数字。10以内的质数有且仅有2、3、5、7。It means a number can only be divided by 1 and itself. Primes that no more than 10 are only 2、3、5 and 7.

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