leetCode-Median of Two Sorted Arrays(binary search)

문제

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.

Example 3:

Input: nums1 = [0,0], nums2 = [0,0] Output: 0.00000

Example 4:

Input: nums1 = [], nums2 = [1] Output: 1.00000

Example 5:

Input: nums1 = [2], nums2 = [] Output: 2.00000

 

Constraints:

• nums1.length == m
• nums2.length == n
• 0 <= m <= 1000
• 0 <= n <= 1000
• 1 <= m + n <= 2000
• -106 <= nums1[i], nums2[i] <= 106

 

---

풀이

const findMedianSortedArrays = function (nums1, nums2) {
    let totalLen = (nums1.length + nums2.length)

    let idx1 = 0;
    let idx2 = 0;
    let curr;
    let last;

    while (idx1 + idx2 <= totalLen / 2) {
        if (curr) {
            last = curr;
        }
        let elOne = nums1[idx1];
        let elTwo = nums2[idx2];
        if (elOne === undefined) {
            curr = elTwo;
            idx2++;
        } else if (elTwo === undefined) {
            curr = elOne;
            idx1++;
        } else if (elOne < elTwo) {
            curr = elOne;
            idx1++;
        } else {
            curr = elTwo;
            idx2++;
        }
        console.log(curr, last);
    }
    return totalLen % 2 === 0 ? (last + curr) / 2 : curr;
};