package class40; public class Code06_RotateMatrix { public static void rotate(int[][] matrix) { int a = 0; int b = 0; int c = matrix.length - 1; int d = matrix[0].length - 1; while (a < c) { rotateEdge(matrix, a++, b++, c--, d--); } } public static void rotateEdge(int[][] m, int a, int b, int c, int d) { int tmp = 0; for (int i = 0; i < d - b; i++) { tmp = m[a][b + i]; m[a][b + i] = m[c - i][b]; m[c - i][b] = m[c][d - i]; m[c][d - i] = m[a + i][d]; m[a + i][d] = tmp; } } public static void printMatrix(int[][] matrix) { for (int i = 0; i != matrix.length; i++) { for (int j = 0; j != matrix[0].length; j++) { System.out.print(matrix[i][j] + " "); } System.out.println(); } } public static void main(String[] args) { int[][] matrix = { { 1, 2, 3, 4 }, { 5, 6, 7, 8 }, { 9, 10, 11, 12 }, { 13, 14, 15, 16 } }; printMatrix(matrix); rotate(matrix); System.out.println("========="); printMatrix(matrix); } }