Median of Two Sorted Arrays

There are two sorted arrays A and B of size m and n respectively. Find the median of the two sorted arrays.
The overall run time complexity should be O(log (m+n)).

For any value in loc i in array A, it takes only O(1) time to determine whether it is the median: only need to check whether there are exact amount of numbers in array B that are less than the value.

class Solution {
    int[] A;
    int[] B;
   
    double median(int A[]){
        if(A.length % 2 == 0)
            return 0.5 * (A[A.length/2 -1] + A[A.length/2]);
        else
            return A[A.length/2];
    }
   
    double med(int small, int large){
        if((A.length + B.length) % 2 == 0)
            return 0.5*(double)(small + large);
        else return Math.max(small,large);
    }
   
    double find(int A[], int B[], int left,int right){
       
        if(left > right) return find(B,A,0,B.length-1);
        int mid = left + (right-left+1)/2;
        int r1 = mid + 1;
        int r2 = (A.length + B.length)/2 - r1;
       
        if(r2 > B.length) return find(A,B,mid+1,right);
        else if (r2 < 0) return find(A,B,left,mid-1);
        else if (r2 == 0){
            if(A[mid] <= B[0]) {
                int min = B[0];
                if(mid+1<A.length) if(min > A[mid+1]) min = A[mid+1];
                return med(A[mid],min);
            }
            else return find(A,B,left,mid-1);
        }
       
        if(B[r2-1] <= A[mid]){
            if(r2 > B.length-1){
                return med(A[mid],A[mid+1]);
            }
            else if(B[r2] >= A[mid]){
                int min = 0;
                if(mid+1>A.length-1){
                    min = B[r2];
                }
                else{
                    min = Math.min(A[mid+1],B[r2]);
                }
                return med(A[mid],min);
               
            }
            else {
                return find(A,B,left,mid-1);
            }
        }
        else{
            return find(A,B,mid+1,right);
        }
       
    }
   
    public double findMedianSortedArrays(int A[], int B[]) {
        // Start typing your Java solution below
        // DO NOT write main() function
        this.A = A; this.B=B;
        if(B.length == 0){
           return median(A);
        }
        else if(A.length == 0) return median(B);
       
        return find(A,B,0,A.length-1);
    }
}