# Right rotation of an array using JAVA

Given an array, right rotate it by k elements.

Examples:

Input: arr[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} k = 3 Output: 8 9 10 1 2 3 4 5 6 7 Input: arr[] = {121, 232, 33, 43 ,5} k = 2 Output: 43 5 121 232 33

Note : In the below solution, k is assumed to be smaller than or equal to n. We can easily modify the solutions to handle larger k values by doing k = k % n
Algorithm:

rotate(arr[], d, n) reverseArray(arr[], 0, n-1) ; reverse(arr[], 0, d-1); reverse(arr[], d, n-1);

Below is the implementation of above approach:

• JAVA

`// Java program for right rotation of`

`// an array (Reversal Algorithm)`

`import` `java.io.*;`

`class` `GFG`

`{`

` ` `// Function to reverse arr[]`

` ` `// from index start to end`

` ` `static` `void` `reverseArray(` `int` `arr[], ` `int` `start,`

` ` `int` `end)`

` ` `{`

` ` `while` `(start < end)`

` ` `{`

` ` `int` `temp = arr[start];`

` ` `arr[start] = arr[end];`

` ` `arr[end] = temp;`

` ` `start++;`

` ` `end--;`

` ` `}`

` ` `}`

` ` `// Function to right rotate`

` ` `// arr[] of size n by d`

` ` `static` `void` `rightRotate(` `int` `arr[], ` `int` `d, ` `int` `n)`

` ` `{`

` ` `reverseArray(arr, ` `0` `, n - ` `1` `);`

` ` `reverseArray(arr, ` `0` `, d - ` `1` `);`

` ` `reverseArray(arr, d, n - ` `1` `);`

` ` `}`

` ` `// Function to print an array`

` ` `static` `void` `printArray(` `int` `arr[], ` `int` `size)`

` ` `{`

` ` `for` `(` `int` `i = ` `0` `; i < size; i++)`

` ` `System.out.print(arr[i] + ` `" "` `);`

` ` `}`

` ` `public` `static` `void` `main (String[] args)`

` ` `{`

` ` `int` `arr[] = {` `1` `, ` `2` `, ` `3` `, ` `4` `, ` `5` `,`

` ` `6` `, ` `7` `, ` `8` `, ` `9` `, ` `10` `};`

` `

` ` `int` `n = arr.length;`

` ` `int` `k = ` `3` `;`

` `

` ` `rightRotate(arr, k, n);`

` ` `printArray(arr, n);`

` `

` ` `}`

`}`

Output:

8 9 10 1 2 3 4 5 6 7