记录-螺旋数组

package Day3;

public class SpiralMatrix {

	public static void main(String[] args) {
		int[][] spiral_array = Spiral_array(3);
		for (int i = 0; i < spiral_array.length; i++) {
			for (int j = 0; j < spiral_array.length; j++) {
				System.out.printf("%d ", spiral_array[i][j]);
			}
			System.out.println();
		}	}


	public static int[][] Spiral_array(int n) {
		int[][] result = new int[n][n];

		if (n < 1) {
			return result;
		}

		int top = 0, right = n - 1, buttom = n - 1, left = 0;
		int i = 1;
		int size = n * n;

		while (size > 0) {
			// 从左到右遍历
			for (int col = left; col <= right; col++) {
				result[top][col] = i;
				size--;
				i++;
			}
			top++;

			// 从顶到底遍历

			for (int row = top; row <= buttom; row++) {
				result[row][right] = i;
				size--;
				i++;
			}
			right--;

			// 从右到左遍历

			for (int row = right; row >= left; row--) {
				result[buttom][row] = i;
				size--;
				i++;
			}
			buttom--;

			// 从底部到顶部

			for (int col = buttom; col >= top; col--) {
				result[col][left] = i;
				size--;
				i++;
			}
			left++;

		}

		return result;
	}

}