Product of Array Exclude Itself

Given an integers array A.

Define B[i] = A[0] * ... * A[i-1] * A[i+1] * ... * A[n-1], calculate B WITHOUT divide operation.

Have you met this question in a real interview? 

Yes

Example

For A = [1, 2, 3], return [6, 3, 2].

public class Solution {

    /**

     * @param A: Given an integers array A

     * @return: A Long array B and B[i]= A[0] * ... * A[i-1] * A[i+1] * ... * A[n-1]

     */

    public ArrayList<Long> productExcludeItself(ArrayList<Integer> A) {

        // write your code

        

        ArrayList<Long> result = new ArrayList<Long>();

        int n = A.size();

        long[] lProducts = new long[n];

        long[] rProducts = new long[n];

        lProducts[0] = (long) 1;

        for(int i = 1; i < A.size(); i++){

            lProducts[i] =  (long)lProducts[i-1]*A.get(i-1);

        }

        rProducts[n-1] = (long) 1;

        for(int i = A.size() - 2; i >= 0 ; i--){

            rProducts[i] = (long)rProducts[i+1]*A.get(i+1);

        }

        for(int i = 0; i < A.size(); i++){

            result.add((long)lProducts[i] * rProducts[i]);

        }

        return result;

    }

}