Rotate Matrix 90 Degrees

This program rotates a matrix by 90 degrees clockwise.

Problem Statement

Write a Java program to rotate a 3x3 matrix by 90 degrees clockwise.

Source Code

1 public class MatrixRotation90 {
2 public static void main(String[] args) {
3 System.out.println("Eduinq Matrix Rotation 90 Degrees");
4 int[][] A = {{1,2,3},{4,5,6},{7,8,9}};
5 int[][] R = new int[3][3];
6 for(int i=0;i<3;i++){
7 for(int j=0;j<3;j++){
8 R[j][3-1-i] = A[i][j];
9 }
10 }
11 for(int i=0;i<3;i++){
12 for(int j=0;j<3;j++){
13 System.out.print(R[i][j]+" ");
14 }
15 System.out.println();
16 }
17 }
18 }

Program Output

Eduinq Matrix Rotation 90 Degrees
7 4 1 
8 5 2 
9 6 3 

Explanation

The rotation requires mapping R[j][n-1-i] = A[i][j], and nested loops perform this transformation, together rotating the matrix clockwise and demonstrating how multidimensional arrays can be rotated.

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