打印“魔方阵”。所谓“魔方阵”是指这样的方阵，它的每一行、每一列和对角线之和均相等。例如，三阶魔方阵为: 8 1 6 3 5 7 4 9 2 要求打印出由1到n*n的自然数构成的魔方阵。-Print "magic matrices." The so-called "magic matrix" refers to the matrix, which each line, each diagonal out and the sum of all the sam