leetcode[4]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)).

double findKth(int A[],int m,int B[],int n,int k)
{
    if(m>n)
    return findKth(B,n,A,m,k);
    if(m==0)
    return B[k-1];
    if(k==1)
    return min(A[0],B[0]);
    int pa=min(k/2,m);
    int pb=k-pa;
    if(A[pa-1]<B[pb-1])
    {
       return findKth(A+pa,m-pa,B,n,k-pa); 
    }
    else if(A[pa-1]>B[pb-1])
    {
       return findKth(A,m,B+pb,n-pb,k-pb);  
    }
    else if(A[pa-1]==B[pb-1])
    {
        return A[pa-1];
    }
}
class Solution {
public:
    double findMedianSortedArrays(int A[], int m, int B[], int n) 
    {
        int total=m+n;
        return (total%2)?(findKth(A,m,B,n,total/2+1)):((findKth(A,m,B,n,total/2)+findKth(A,m,B,n,total/2+1))/2);
    }
};

 

posted @ 2015-02-10 13:57  Vae永Silence  阅读(138)  评论(0编辑  收藏  举报