數獨~~ - 數獨

原題　

5xx xxx xx9
6xx 4xx xxx
xx4 x92 x3x

x1x xx3 x6x
xx6 x2x 9xx
x3x 9xx x7x

x6x 74x 1xx
xxx xx8 xx6
2xx xxx xx5

解得

5xx xxx 4x9
6xx 4xx xxx
1x4 592 63x

x1x 8x3 x64
xx6 12x 9x3
x3x 9xx x71

36x 74x 1xx
xxx 2x8 xx6
2xx xxx xx5

然後想了很久還是卡住
請高手提示下一步.謝謝
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