Leetcode 4. Median of Two Sorted Arrays(java版)

题目:

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)).

题目大意：

给两个已排序的数组，求两个数组合中所有元素的中位数。

example1：

nums1 = [1, 3]
nums2 = [2]

The median is 2.0

example2:

nums1 = [1, 2]
nums2 = [3, 4]

The median is (2 + 3)/2 = 2.5

思路：

我想到了数组的归并，用归并的思想将数组合并，然后求中位数。

代码：

class Solution {    public double findMedianSortedArrays(int[] nums1, int[] nums2) {        int n = nums1.length;        int m = nums2.length;        //System.out.printf("%d %d\n",n,m);        int[] nums3 = new int[m+n];        int i = 0, j = 0, k = 0;        while(i < n && j < m) {            if(nums1[i] <= nums2[j]) {                nums3[k] = nums1[i];                i++;                k++;            }            else {                nums3[k] = nums2[j];                j++;                k++;            }        }        if(i == n) {            for(; j < m; j++) {                nums3[k] = nums2[j];                k++;            }           }        if(j == m) {            for(; i < n; i++) {                nums3[k] = nums1[i];                k++;            }                }        int temp = (n + m) / 2;        //System.out.println(temp);        double ans = 0.0;        if((n + m) % 2 == 0) {            ans = (nums3[temp-1] + nums3[temp]) / 2.0;        }        else {            ans = nums3[temp];        }        return ans;    }}