Java program to rotate a matrix to 90 degree - amazon interview questions

/**
 * Amazon interview question rotating a matrix to 90 degree
 */
package com.cfed.amazon;

/**
 * @author Konzernties
 *
 */
public class RotateMatrix {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub

int ar[][] = new int[3][3];
int val = 0;
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
ar[i][j] = ++val;
}
}

for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
System.out.print(ar[i][j]+" ");
}
System.out.println();
}

System.out.println(" Rotated 90 degree to left ");

for (int j = 2; j >= 0; j--) {
for (int i = 0; i < 3; i++) {
System.out.print(ar[i][j]+" ");
}
System.out.println();
}
}
}

Output

1 2 3 

4 5 6 

7 8 9 

 Rotated 90 degree to left 

3 6 9 

2 5 8 

1 4 7

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