Partition-and-Recur (PAR) method is a simple and useful formal method. It can be used to design and testify algo-rithmic programs. In this paper, we propose that PAR method is an effective formal method on solving com...Partition-and-Recur (PAR) method is a simple and useful formal method. It can be used to design and testify algo-rithmic programs. In this paper, we propose that PAR method is an effective formal method on solving combinatorics problems. Furthermore, we formally derive combinatorics problems by PAR method, which cannot only simplify the process of algorithmic program's designing, but also improve its automatization, standardization and correctness. We develop algorithms for two typical combinatorics problems, the number of string scheme and the number of error per-mutation scheme. Lastly, we obtain accurate C++ programs which are transformed by automatic transforming system of PAR platform.展开更多
国家教育部制定的高中新课程标准将算法初步作为高中数学课程的必修内容,算法与程序设计也首次纳入到选修课之列。全国大部分普通高中均按新课标开展教学实验,不少省份还把算法内容纳入高考。同时现有算法初步和算法与程序设计教材在介...国家教育部制定的高中新课程标准将算法初步作为高中数学课程的必修内容,算法与程序设计也首次纳入到选修课之列。全国大部分普通高中均按新课标开展教学实验,不少省份还把算法内容纳入高考。同时现有算法初步和算法与程序设计教材在介绍算法与算法设计方法时,无法说清楚算法设计的过程;在教学实践中,这一问题更加突出。这给高中生学习、理解及掌握算法和算法设计方法带来很大的困难。本文从新课程实验教材中及数学高考题中选取两个问题,用支持算法程序形式化开发的PAR(Partition And Recur)方法与PAR平台,从待求解问题的精确功能描述出发,经过一系列等价数学变换,最后得到正确的算法和程序。实践说明PAR方法与PAR平台可以在高中算法教学及学生能力评测中发挥建设性作用。展开更多
文摘Partition-and-Recur (PAR) method is a simple and useful formal method. It can be used to design and testify algo-rithmic programs. In this paper, we propose that PAR method is an effective formal method on solving combinatorics problems. Furthermore, we formally derive combinatorics problems by PAR method, which cannot only simplify the process of algorithmic program's designing, but also improve its automatization, standardization and correctness. We develop algorithms for two typical combinatorics problems, the number of string scheme and the number of error per-mutation scheme. Lastly, we obtain accurate C++ programs which are transformed by automatic transforming system of PAR platform.
文摘国家教育部制定的高中新课程标准将算法初步作为高中数学课程的必修内容,算法与程序设计也首次纳入到选修课之列。全国大部分普通高中均按新课标开展教学实验,不少省份还把算法内容纳入高考。同时现有算法初步和算法与程序设计教材在介绍算法与算法设计方法时,无法说清楚算法设计的过程;在教学实践中,这一问题更加突出。这给高中生学习、理解及掌握算法和算法设计方法带来很大的困难。本文从新课程实验教材中及数学高考题中选取两个问题,用支持算法程序形式化开发的PAR(Partition And Recur)方法与PAR平台,从待求解问题的精确功能描述出发,经过一系列等价数学变换,最后得到正确的算法和程序。实践说明PAR方法与PAR平台可以在高中算法教学及学生能力评测中发挥建设性作用。