Rotate Array in clock Wise

What is Array Rotation?

Array rotation is the process of shifting the elements of an array to new positions by a certain number of times (k).

There are two types of array rotation:

• Clockwise rotation (Right rotation / Right shift)

• Anti-clockwise rotation (Left rotation / left shift)

What is Clockwise Rotation?

Clockwise rotation means shifting the array elements to the right.
In this process, the last element moves to the first position, and all other elements shift one position to the right.

• Step for clock wise rotation

Step 1: Reverse whole array

Step 2: Reverse first k elements (0 to k-1)

Step 3: Reverse elements from k to (size-1)

class Main {
public static void reverseArray(int [] arr , int sIndex , int eIndex){
    while(sIndex<eIndex){
        arr[sIndex ]=(arr[sIndex ]+arr[eIndex ])-(arr[eIndex ]=arr[sIndex ]);
        sIndex++; eIndex--;
    }


    }
    public static void main(String[] args) {
        int [] num = {10,20,30,40,50};
        int k =2;
        k = k%num.length;
         System.out.println("original Array : ");
        for(int i = 0 ; i<num.length;i++){
            System.out.print(num[i]+" ");
        }
        // step 1 
        reverseArray(num , 0 , num.length-1);
        //step 2 
        reverseArray(num , 0 , k-1);
        // step 3 
        reverseArray(num ,k, num.length-1);

        System.out.println();
        System.out.println("After "+k+"th clock wise rotation : ");
        for(int i = 0 ; i<num.length;i++){
            System.out.print(num[i]+" ");
        }

    }
}

Output :

original Array : 
1 2 3 4 5 
After 2th clock wise rotation : 
4 5 1 2 3