Intersection of Two Arrays II

Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must appear as many times as it shows in both arrays and you may return the result in any order.

LeetCode Problem - 350

class Solution {
    // Method to find the intersection of two arrays
    public int[] intersect(int[] nums1, int[] nums2) {
        List<Integer> answerList = new ArrayList<>(); // List to store intersecting elements

        // Iterate through nums1 array
        for(int i=0; i<nums1.length; i++){
            int e = nums1[i]; // Current element from nums1
            // Iterate through nums2 array
            for(int j=0; j<nums2.length; j++){
                int k = nums2[j]; // Current element from nums2
                // If elements match and nums2 element is not marked as used (-1),
                // add to answerList and mark nums2 element as used
                if(e == k && nums2[j] != -1){
                    answerList.add(e);
                    nums2[j] = -1; // Mark nums2 element as used
                    break; // Move to the next element in nums1
                }
            }
        }

        // Convert answerList to an integer array
        int[] answer = new int[answerList.size()];
        for(int i=0; i<answer.length; i++){
            answer[i] = answerList.get(i); // Copy elements from answerList to answer array
        }

        return answer; // Return the intersection array
    }
}