Merge Sorted Array

by atalaykutlay

Solution for merge sorted array question on Leetcode.

Merge Sorted Array

1class Solution:
2    def merge(self, nums1: List[int], m: int, nums2: List[int], n: int) -> None:
3        """
4        Do not return anything, modify nums1 in-place instead.
5        """
6        left = m-1
7        right = n-1
8        for i in range(m+n-1, -1, -1):
9            if left >= 0 and right >= 0 and nums1[left] > nums2[right]:
10                nums1[i] = nums1[left]
11                left -= 1
12            elif right >= 0:
13                nums1[i] = nums2[right]
14                right -= 1
15

✨ Code Explanation ✨

This code is a solution to the Leetcode problem titled "Merge Sorted Array." The function takes in two sorted arrays, 'nums1' and 'nums2' and their respective lengths 'm' and 'n'. The goal of the function is to merge 'nums2' into 'nums1' and ensure the result is still sorted. The function begins by initializing two pointers, 'left' and 'right'. These two pointers are set to the end of 'nums1' and 'nums2' respectively. A 'for' loop is then used to iterate through a range of indices from 'm+n-1' to 0, both inclusive, in reverse order. Within the loop, each value of 'nums1' at the current index 'i' is then assigned either the current value of 'nums1' at index 'left' or 'nums2' at index 'right'. If 'nums1[left]' is greater than 'nums2[right]' and both pointers are still within their respective arrays, 'nums1[i]' will be assigned 'nums1[left]' and 'left' will be decremented by 1. If 'nums1[left]' is not greater than 'nums2[right]', then 'nums1[i]' will be assigned 'nums2[right]' and 'right' will be decremented by 1. Once all values have been assigned, 'nums1' will contain the merged sorted array of 'nums1' and 'nums2' and the function will terminate.