笛卡儿乘积是以有序偶为元素组成的集合，对给定的集合A和B，求笛卡儿乘积，只需取尽由集合A的元素及集合B的元素，并构成序偶
送入C之中即可。-Cartesian product even as the elements in an orderly set of a given set A and B, seeking Cartesian product, simply take to do by the collection A collection of elements and the elements of B and constitutes a sequence duality " ai, bj> being sent to C can be. 
