Program for array rotation | Code Factory

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Write a function rotate(array[], x) that rotates array[] of size n by x elements.

| 1 | 2 | 3 | 4 | 5 |

Rotation of the above array by 2 will make array

| 3 | 4 | 5 | 1 | 2 |

Please first try to do it yourself, then move to the solution.

1) Rotate array from x to length and store elements into newArray.
2) Rotate array from 0 to x and store elements into newArray.

Program

package com.test;

import java.util.Arrays;

/**
 * @author code.factory
 */
public class Test {
	public static void main(String... strings) {
		int array[] = new int[] {10, 20, 30, 40, 50};
		rotate(array, 0);
		rotate(array, 34);
		rotate(array, 3);
	}

	static void rotate(int array[], int x) {
		int length = array.length;
		int newArray[] = new int[length];
		x = x % length; // set x to b/w o to length of array so it will not traverse more

		// Rotate array using 2 loop
		for (int i = x; i < length; i++) {
			newArray[i - x] = array[i];
		}
		for (int j = 0; j < x; j++) {
			newArray[length - x + j] = array[j];
		}
		
		System.out.println(Arrays.toString(newArray));
		newArray = new int[length];

		// Rotate array using 1 loop
		for (int j = 0; j < length; j++) {
			if (j >= x) {
				newArray[j - x] = array[j];
			} else {
				newArray[length - x + j] = array[j];
			}
		}
		System.out.println(Arrays.toString(newArray));
	}
}

Output:

[10, 20, 30, 40, 50]
[10, 20, 30, 40, 50]

[50, 10, 20, 30, 40]
[50, 10, 20, 30, 40]

[40, 50, 10, 20, 30]
[40, 50, 10, 20, 30]