螺旋方阵

输入有多组数据，每组只有一行，包含x,y(1 <= x,y <= 30)和t，输出x*y螺旋方阵，如果t=0，就输出逆时针螺旋方阵，否则输出顺时针的

样例输出（每个数字要占四个格子，输出完一组就接着输出一个空行）：
   1  12  11
   2  13  10
   3  14   9
   4  15   8
   5   6   7

   1   2   3   4
  12  13  14   5
  11  16  15   6
  10   9   8   7

#include <iostream>

#include <iomanip>

using namespace std;

int main()

{

    int M,N;

         cout << "输入每行个数N：";

    cin >> N;

         cout << "输入每列个数M：";

    cin >> M;

         int up = 0;      //上边界

         int down = M-1; //下边界

         int left = 0;    //左边界

         int right = N-1;   //右边界

         int num = 1;    //从一开始累加

         int array[20][20];

    int t;

         cout << "0-----逆时针输出：/n其他--顺时针输出/n输入：";

         cin >> t;

    if (t != 0)

         {

               for (;up <= down, left <= right; up ++, down --, left ++, right --)

                   {

                 for (int i = left; i <= right; i ++) array[up][i] = num ++;

                 for (i = up + 1; i < down; i ++) array[i][right] = num ++;

                 for (i = right ; i >= left; i --) array[down][i] = num ++;

                 for (i = down-1 ; i > up; i --) array[i][left] = num ++;

                   }     

         }

 

         else if (t == 0)

         {

             for (;up < down, left <= right; up++, down --, left ++, right --)

                   {

                 for (int i = up; i <= down; i ++) array[i][left] = num++;

                 for (i = left + 1; i < right; i ++) array[down][i] = num++;

                 for (i = down; i >= up; i --) array[i][right] = num ++;

                 for (i = right - 1; i >left; i --) array[up][i] = num ++;

                   }

         }

         for (int i = 0; i < M; i ++)

                   {

                  for (int j = 0; j < N; j ++)

                       cout << setw(4) << array[i][j];

               cout << endl;

                   }

         return 0;

}