LeetCode每日一题：median of two sorted arrays

问题描述

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)).

问题分析

这题的难度是怎么在O(log (m+n))的复杂度内解决，最后抄了个答案，实在没想出来。

代码实现

public double findMedianSortedArrays(int A[], int B[]) {
        double median_fir = 0;
        int m = A.length, n = B.length;
        if (A == null || B == null || m + n == 0) {
            return 0;
        }
        int indexA = 0, indexB = 0;
        while (indexA + indexB != (m + n + 1) / 2) {
            int a = (indexA == m) ? Integer.MAX_VALUE : A[indexA];
            int b = (indexB == n) ? Integer.MAX_VALUE : B[indexB];
            if (a < b) {
                median_fir = a;
                indexA++;
            } else {
                median_fir = b;
                indexB++;
            }
        }
        if ((m + n) % 2 == 1)
            return median_fir;
        else {
            int temp_a = (indexA == m) ? Integer.MAX_VALUE : A[indexA];
            int temp_b = (indexB == n) ? Integer.MAX_VALUE : B[indexB];
            double median_sec = (temp_a < temp_b) ? temp_a : temp_b;
            return (median_fir + median_sec) / 2;
        }
    }