70岁刘瑞侠在窗外认真听课。本版照片由马志亚摄影 刘瑞侠教孙子认识盲文。
Can anyone suggest how to solve the Log Pile wooden puzzle using a computer program? See here to visualise the puzzle: http://www.puzzlethis.co.uk/products/madcow/the_log_pile.htm
加载中,请稍侯......