Merge Sorted Array-LeetCode

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 andn respectively.

class Solution {
public:
    void merge(int A[], int m, int B[], int n)
    {
        if (m == 0)
            for (int i = 0; i < n; i++)
                A[i] = B[i];
	   else
	   {
		  int count = n + m - 1;
		  int i = m - 1, j = n - 1;
		  int x;
		  for (x = count; x >= 0 && j >= 0 && i >=0; x-- )
		  {
			 if (B[j] >= A[i])
				A[x] = B[j--];	
			 else
			    A[x] = A[i--];
		  }
	
		  if (i < 0)
			 while(j >= 0)
			    A[x--] = B[j--];
	   }
    }

};