顺时针方向打印矩阵

/************************************************************************/
/* 
	顺时针方向由外向内打印矩阵
	矩阵规格：m * n，m 行 n 列
	cur ： 当前打印的是第几次打印，即第几圈（由外向内数，从0开始递增）
*/
/************************************************************************/
void printMetrix(int **metrix,int m,int n,int cur)
{
	if(m < cur << 1 && n < cur << 1)
	{
		return;
	}
	
	//top row
	int topRowCounts = n - (cur<<1) - 1;		//top 行最末尾一个不打印，留到 right 列去打印
	if(topRowCounts > 0)
	{
		int *topRow = (*(metrix + cur) + cur);
		while(topRowCounts --)
		{
			printf("%d  ",*(topRow ++));
		}
	}

    //right field
	int rightFieldCounts = m - (cur<<1) - 1;	//right 列最末尾一个不打印，留到 bottom 行去打印
	if(rightFieldCounts > 0)
	{
		int **rightField = metrix + cur;
		while(rightFieldCounts --)
		{
			printf("%d  ",*(*(rightField ++) + n - 1 - cur));
		}
	}

	//bootom row
	int bottomRowCounts = n - (cur<<1) - 1;		//bootom 行最末尾一个不打印，留到 left 列去打印
	if(bottomRowCounts > 0)
	{
		int *bottomRow = (*(metrix + n - 1 - cur) + m - 1 - cur);
		while(bottomRowCounts --)
		{
			printf("%d  ",*(bottomRow --));
		}
	}
	
	//left field
	int leftFieldCounts = m - (cur<<1) - 1;		//left 列最末尾一个已由本轮中的 top 行打印过了
	if(leftFieldCounts > 0)
	{
		int **leftField = metrix + n - 1 - cur;
		while(leftFieldCounts --)
		{
			printf("%d  ",*(*(leftField --) + cur));
		}
	}
	
	//递归打印
	printMetrix(metrix,m,n,cur + 1);
}


typedef int (*ARRAYPOINT)[4];
int _tmain(int argc, _TCHAR* argv[])
{
	int metrix[4][4] = {{1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16}};
	ARRAYPOINT t = metrix;
	int *p [4] = {(int *)t,(int *)(t + 1),(int *)(t + 2),(int *)(t + 3)};
	int **s = (int **)p;	//由二维矩阵转换为二维指针，见文章说明
	
	printMetrix(s,4,4,0);
	system("PAUSE");
	return 0;
}