Leetcode-Merge Sorted Array

Given two sorted integer arrays A and B, merge B into A as one sorted array.

Note:
You may assume that A has enough space (size that is greater or equal to m + n) to hold additional elements from B. The number of elements initialized in A and B are m and n respectively.

Solution:

public class Solution {
    public void merge(int A[], int m, int B[], int n) {
        int end = m+n-1;
        int index1=m-1, index2=n-1;
        
        while (end>=0){
            if (index1<0){
                A[end]=B[index2];
                index2--;
                end--;
            } else if (index2<0){
                break;
            } else {
                if (A[index1]>B[index2]){
                    A[end] = A[index1];
                    index1--;
                    end--;
                } else {
                    A[end] = B[index2];
                    index2--;
                    end--;
                }
            }
        }
    }
}