How can we rotate an array to the left?

Rotating to the left by n is the same as rotating to the right by length-n.

Rotate right (for positive n):

for(int i = 0; i < data.length; i++){    result[(i+n) % data.length ] = data[i];}

Rotate left (for positive n):

for(int i = 0; i < data.length; i++){    result[(i+(data.length-n)) % data.length ] = data[i];}

This way you can avoid a modulo of a negative number.

If you want to input an integer n that rotates right if n is positive and left if n is negative, you can do it like this:

 int[] rotateArray(int n, int[] data) {      if(n < 0) // rotating left?      {          n = -n % data.length; // convert to +ve number specifying how                                 // many positions left to rotate & mod          n = data.length - n;  // rotate left by n = rotate right by length - n      }      int[] result = new int[data.length];      for(int i = 0; i < data.length; i++){          result[(i+n) % data.length ] = data[i];      }      return result; }

In case rotate to the left, you can use this to avoid a modulo of a negative number:

int[] data = {1, 2, 3, 4, 5};int[] result = new int[data.length];for (int i = 0; i < data.length; i++) {    result[(i + (data.length - 2)) % data.length] = data[i];}for (int i : result) {    System.out.println(i);}

You may also use linkedlist to achieve the same.

Integer[] arr = {1,2,3,4,5};        LinkedList<Integer> ns = new LinkedList<Integer>(Arrays.asList(arr));        int rotate=3;        if(rotate<0)            rotate += arr.length;        List<Integer> leftlist = ns.subList(0, rotate);        List<Integer> rightlist = ns.subList(rotate, arr.length);        LinkedList<Integer> result = new LinkedList<Integer>();        result.addAll(rightlist);        result.addAll(leftlist);        System.out.println(result);