LeetCode problem : Median of Two Sorted Arrays

Problem

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)).

Code

double fmsa(int A[], int m, int B[], int n,int rank) {
    // Note: The Solution object is instantiated only once and is reused by each test case.
    if(n > m)
        return fmsa(B,n,A,m,rank);
    if(n == 0)
        return A[rank - 1];
    if(rank == 1)
        return min(B[0],A[0]);
    int k = min(n,rank/2);
    if(A[k - 1] < B[k - 1]){
        A += k;
        m -= k;
    }
    else{
        B += k;
        n -= k;
    }
    rank -= k;
    return fmsa(A,m,B,n,rank);
}
double findMedianSortedArrays(int A[], int m, int B[], int n) {
    // Note: The Solution object is instantiated only once and is reused by each test case.
    int rank = (m + n)/2;
    if((m + n) % 2 == 0){
        return ( fmsa(A,m,B,n,rank) + fmsa(A,m,B,n,rank + 1) )/2.0;
    }
    else
        return fmsa(A,m,B,n,rank + 1);
}