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 to hold additional elements from B. The number of elements initialized in A and B are m and n respectively.

public class Solution {
    public void merge(int A[], int m, int B[], int n) {
        // IMPORTANT: Please reset any member data you declared, as
        // the same Solution instance will be reused for each test case.
        int k = m + n - 1, i = m - 1, j = n - 1;
        while(i >= 0 || j >= 0){
            if(i >= 0 && (j < 0 || A[i] > B[j])) A[k--] = A[i--];
            else A[k--] = B[j--];
        }
    }
}