leetcode 4. 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

意思是在两个已排序的int数组中找到一个中位数,思路是:可以用归并排序的merge方法，将两个排好序的数组排成一个有序的数组b，在b中找中位数。

code:

class Solution {
    public double findMedianSortedArrays(int[] nums1, int[] nums2) {
        int length=nums1.length+nums2.length;
        int a[]=new int[length];
        int p1=0;
        int p2=0;
        for(int i=0;i<length;i++)
        {
            if(p1==nums1.length) a[i]=nums2[p2++];
            else if(p2==nums2.length) a[i]=nums1[p1++];
            else if(nums1[p1]>nums2[p2]) a[i]=nums2[p2++];
            else a[i]=nums1[p1++];
        }
        if(length%2==1){
            return a[length/2];
        }else
            return ((a[length/2]+a[length/2-1])/2.0);
    }
}