ClassMergeSort

//https://pastebin.com/hy6Q7DwU  -> MergeSortMain
package MergeSort18313;

public class DivideAndCompare {
    void merge(int arr[], int left, int mid, int right)
    {

        int l = mid - left + 1;
        int r = right - mid;

        int LeftArray[] = new int [l];
        int RightArray[] = new int [r];

        for (int i=0; i < l; ++i)
            LeftArray[i] = arr[left + i];
        for (int j=0; j < r; ++j)
            RightArray[j] = arr[mid + 1+ j];
        //split to 2 new arrays;

        int i = 0, j = 0;
        int k = left;
        while (i<l && j<r)
        {
            if (LeftArray[i] <= RightArray[j])
            {
                arr[k] = LeftArray[i];
                i++;
            }
            else
            {
                arr[k] = RightArray[j];
                j++;
            }
            k++;
        }
        //compare the arrays and checking higher num

        while (i<l)
        {
            arr[k] = LeftArray[i];
            i++;
            k++;
        }
        //checking if left array is shorter than right ones

        while (j<r)
        {
            arr[k] = RightArray[j];
            j++;
            k++;
        }
        //checking if right array is shorter than left ones
        //end of merge method
    }

    public void Sort(int arr[], int l, int r)
    {
        if (l < r)
        {
            int mid = (l + r)/2; //setting the mid index
            Sort(arr, l, mid);
            Sort(arr , mid+1, r);
            merge(arr, l, mid, r);
        }
    }
}