输入一个自然数Ｎ（2≤N≤9），要求输出如下的螺旋矩阵，即边长为N*N，元素取值为1至N*N，1在左上角，呈顺时针方向依次放置各元素。



N=3时，相应的矩阵中每个数字位置如下图所示：



1 2 3



8 9 4



7 6 5-Enter a natural number N (2 ≤ N ≤ 9), the requirements are as follows spiral output matrix, that is, edge length of N* N, the element values for the 1 to N* N, 1 in the upper left corner, showing a clockwise direction in order to place the various elements . N = 3, the corresponding figures for the location of each matrix as follows: 123,894,765