螺旋矩阵的实现，从键盘输入一个整数（1~20） 则以该数字为矩阵的大小，把1,2,3…n*n 的数字按照顺时针螺旋的形式填入其中-Spiral Matrix in, enter an integer from the keyboard (1 ~ 20) are indicated in the figure for the size of the matrix, the 1,2,3 ... n* n the number of forms filled in accordance with