004 Median of Two Sorted Arrays ⭐

There are two sorted arrays nums1 and nums2 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)).

Example 1:

nums1 = [1, 3]nums2 = [2]The median is 2.0

Example 2:

nums1 = [1, 2]nums2 = [3, 4]The median is (2 + 3)/2 = 2.5

class Solution(object):    def findMedianSortedArrays(self, A, B):        """        :type nums1: List[int]        :type nums2: List[int]        :rtype: float        """        m,n=len(A),len(B)        if m>n:            A,B,m,n=B,A,n,m        imin=0        imax=m        halflen=(m+n+1)/2        while imin<=imax:            i=(imin+imax)/2            j=halflen-i            if i<m and B[j-1]>A[i]:                imin=i+1            elif i>0 and A[i-1]>B[j]:                imax=i-1            else:                if i==0:                    lmax=B[j-1]                elif j==0:                    lmax=A[i-1]                else:                    lmax=max(A[i-1],B[j-1])                if (m+n)%2==1:                    return lmax                if i == m:                     rmin = B[j]            elif j == n:                     rmin = A[i]            else:                     rmin = min(A[i], B[j])                return (lmax + rmin)/2.0        

这题挺难，看了答案，这个二分法的思路挺精巧