88. Merge Sorted Array

문제 설명

You are given two integer arrays nums1 and nums2, sorted in non-decreasing order, and two integers m and n, representing the number of elements in nums1 and nums2 respectively.

Merge nums1 and nums2 into a single array sorted in non-decreasing order.

The final sorted array should not be returned by the function, but instead be stored inside the array nums1. To accommodate this, nums1 has a length of m + n, where the first m elements denote the elements that should be merged, and the last n elements are set to 0 and should be ignored. nums2 has a length of n.

Example

example 1

Input: nums1 = [1,2,3,0,0,0], m = 3, nums2 = [2,5,6], n = 3
Output: [1,2,2,3,5,6]
Explanation: The arrays we are merging are [1,2,3] and [2,5,6].
The result of the merge is [1,2,2,3,5,6] with the underlined elements coming from nums1.

example 2

Output: [1]
Explanation: The arrays we are merging are [1] and [].
The result of the merge is [1].

example 3

Input: nums1 = [0], m = 0, nums2 = [1], n = 1
Output: [1]
Explanation: The arrays we are merging are [] and [1].
The result of the merge is [1].
Note that because m = 0, there are no elements in nums1. The 0 is only there to ensure the merge result can fit in nums1.

Idea

nums1 배열에 있는 0 을 없애주고 나서 nums2를 nums1 배열에 스프레드 연산자를 사용해 삽입한 후 정렬한값을 반환한다

Solution

var merge = function(nums1, m, nums2, n) {
    const len =m+n
    for(let i = len-1 ; i>=m; i--){
        if(nums1[i] === 0){
            nums1.pop()
        }else break
    }
    nums1.push(...nums2)
    nums1.sort((a,b)=>a-b)
};

다른사람 풀이

var merge = function(nums1, m, nums2, n) {
    let insertPos = m + n - 1;
    m--; n--;
    while (n >= 0) {
        nums1[insertPos--] = (nums1[m] > nums2[n]) ? nums1[m--] : nums2[n--];
    }
};