排列与组合是当今发展很快的组合数学最初步、最基本的知识,它不仅应用广泛,同时也是学习概率统计知识以及进一步学习高等数学有关分支的必要准备.由于其思维方法独特,解法又灵活且极易与其它科目、日常生活联系,也极易与数学其 Arrangement and combination is the most basic and basic knowledge of the rapid development of combinatorial mathematics. It is not only widely used, but also a necessary preparation for learning probability statistics and further learning related branches of higher mathematics. Due to its unique thinking method, the solution is flexible. And it is easy to contact with other subjects and daily life, and it is also very easy with mathematics.