[LeetCode] 88. Merge Sorted Array

Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array.
Note:
You may assume that nums1 has enough space (size that is greater or equal to m + n) to hold additional elements from nums2. The number of elements initialized in nums1 and nums2 are m and n respectively.

Thought process:
Start from the ends of two arrays and merge to the end of nums1.

Solution:
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public class Solution {
    public void merge(int[] nums1, int m, int[] nums2, int n) {
        int i = m - 1;
        int j = n - 1;
        
        while (i >= 0 && j >= 0) {
            if (nums1[i] > nums2[j]) {
                nums1[i + j + 1] = nums1[i];
                i--;
            } else {
                nums1[i + j + 1] = nums2[j];
                j--;
            }
        }
        
        if (j >= 0) {
            for (; j >= 0; j--) {
                nums1[j] = nums2[j];
            }
        }
    }
}

Time complexity: O(m + n).
Location: San Jose, CA, USA

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