螺旋矩阵代码,Java代码库,德仔网

代码语言
代码分类
【Java】螺旋矩阵
作者:孩时风光 / 发布于2015/4/8/ 535

	public class Test
	{
	 /**
	 * 产生螺旋矩阵
	 * @param n
	 * @return
	 */
	 public static int[][] spiralMatrix(int n)
	 {
	 int root = rootOf(n);
	 if (0 == root)
	 {
	 return null;
	 }
	 int[][] result = new int[root][root];
	 fillFirstRow(root, result);
	 //第一行填充之后游标的位置;
	 int x = root - 1;
	 int y = 0;
	 //每次移动的增量
	 int[] direction = {0, 1};
	 int steps = root - 1;
	 boolean stepsDecrise = false;
	
	 for (int i = root + 1; i <= n;)
	 {
	 for (int step = 0; step < steps; step++)
	 {
	 x += direction[0];
	 y += direction[1];
	 result[y][x] = i;
	 i++;
	 }
	 turn(direction);
	 //转向两次,步长减一;
	 if (stepsDecrise)
	 {
	 steps--;
	 }
	 stepsDecrise = !stepsDecrise;
	 }
	 return result;
	 }
	
	 /**
	 * 填充矩阵的第一行
	 * @param root
	 * @param result
	 */
	 private static void fillFirstRow(int root, int[][] result)
	 {
	 for (int i = 0; i < root; i++)
	 {
	 result[0][i] = i + 1;
	 }
	 }
	
	 /**
	 * 求n的平方根
	 * @param n
	 * @return 如果平方根是整数,返回平方根,否则返回0;
	 */
	 private static int rootOf(int n)
	 {
	 for (int i = 1; i * i <= n; i++)
	 {
	 if (i * i == n)
	 {
	 return i;
	 }
	 }
	 return 0;
	 }
	
	 /**
	 * 转向:修改方向数组的值
	 * @param direction
	 */
	 private static void turn(int[] direction)
	 {
	 if (direction[0] == 0 && direction[1] == 1)
	 {
	 direction[0] = -1;
	 direction[1] = 0;
	 }
	 else if (direction[0] == 0 && direction[1] == -1)
	 {
	 direction[0] = 1;
	 direction[1] = 0;
	 }
	 else if (direction[0] == 1 && direction[1] == 0)
	 {
	 direction[0] = 0;
	 direction[1] = 1;
	 }
	 else if (direction[0] == -1 && direction[1] == 0)
	 {
	 direction[0] = 0;
	 direction[1] = -1;
	 }
	 }
	
	 /**
	 * 打印矩阵
	 * @param matrix
	 */
	 private static void printMatrix(int[][] matrix)
	 {
	 for (int[] row : matrix)
	 {
	 for (int i : row)
	 {
	 System.out.format("%d ", i);
	 }
	 System.out.println();
	 }
	 }
	
	 public static void main(String[] args)
	 {
	 printMatrix(spiralMatrix(4));
	 printMatrix(spiralMatrix(9));
	 printMatrix(spiralMatrix(16));
	 printMatrix(spiralMatrix(25));
	 }
	}
试试其它关键字
　螺旋矩阵　
同语言下
可能有用的
孩时风光贡献的其它代码(3)