数独81格的解题方法和技巧

简介：The two of them were walking side by side in the courtyard of the community. The ground near the corner was covered with yellowing sand. The leaves of several large banyan trees in the courtyard were all a little yellow. The cold wind blew over and the yellow leaves swirled down, creating a picture of autumn. The chilly and desolate look, even though it was one or two thirty in the afternoon, it was cloudy and the sun was hidden in the clouds. ．??`