4. Median of Two Sorted Arrays

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題目敘述

Given two sorted arrays nums1 and nums2 of size m and n respectively, return the median of the two sorted arrays.

The overall run time complexity should be O(log (m+n)).

Example 1

Input: nums1 = [1,3], nums2 = [2] Output: 2.00000 Explanation: merged array = [1,2,3] and median is 2.

Example 2

Input: nums1 = [1,2], nums2 = [3,4] Output: 2.50000 Explanation: merged array = [1,2,3,4] and median is (2 + 3) / 2 = 2.5.

解題思路

Solution

import java.util.Arrays;

class Solution {
    public double findMedianSortedArrays(int[] nums1, int[] nums2) {
        int[] nums = new int[nums1.length + nums2.length];
        int index = 0;

        for (int num : nums1) {
            nums[index++] = num;
        }

        for (int num : nums2) {
            nums[index++] = num;
        }

        Arrays.sort(nums);
        double ans = 0;
        int len = nums.length;

        if (len % 2 == 0) {
            ans = (nums[len / 2 - 1] + nums[len / 2]) / 2.0;
        } else {
            ans = nums[len / 2];
        }

        return ans;
    }
}