int[] left = Arrays.copyOfRange(arr, l, m + 1);
In Java, the copyOfRange() method of the Arrays class is used to create a copy of a range of elements from an array. It has the following syntax:
int[] copyOfRange(int[] original, int from, int to)
The original parameter is the original array, and the from and to parameters specify the range of elements to be copied. The from index is inclusive and the to index is exclusive, so the range includes all elements from the from index to the to index-1.
For example, the following code creates a copy of a range of elements from an array:
int[] arr = {1, 2, 3, 4, 5};
int l = 1;
int m = 3;
int[] left = Arrays.copyOfRange(arr, l, m + 1);
// left is {2, 3, 4}
The copyOfRange() method is a useful utility for creating subarrays and for performing operations on a specific range of elements in an array.
For more information on the copyOfRange() method in Java, you can refer to the Java documentation.