题目

题解

代码

/** * code48 */
public class code48 {

    public static void rotate(int[][] matrix) {
        int n = matrix.length;

        // transpose matrix
        for (int i = 0; i < n; i++) {
            for (int j = i; j < n; j++) {
                int temp1 = matrix[i][j];
                matrix[i][j] = matrix[j][i];
                matrix[j][i] = temp1;
            }
        }

        // reverse each row
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n / 2; j++) {
                int temp2 = matrix[i][j];
                matrix[i][j] = matrix[i][n - j - 1];
                matrix[i][n - j - 1] = temp2;
            }
        }
    }

    public static void main(String[] args) {
        // int matrix[][] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } };
        int matrix[][] = { { 5, 1, 9, 11 }, { 2, 4, 8, 10 }, { 13, 3, 6, 7 }, { 15, 14, 12, 16 } };

        rotate(matrix);

        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix.length; j++) {
                System.out.print(matrix[i][j] + " ");
            }
            System.out.println();
        }
    }
}
48. 旋转图像

题目

题解

代码

参考
