Merge Sorted Array 題解

題目來源：https://leetcode.com/problems/merge-sorted-array/description/

Description

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.

Solution

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

解題描述

這道題題意是，給出兩個排好序的數組nums1和nums2，分別包含m、n個數字，nums1總的空間不小於m + n，要求合並兩個數組，將結果存在nums1中。也就是說，空余的空間一開始是在nums1數組的尾部，算法就是從大到小進行歸並，將結果依次插入到nums1尾部即可，這樣就不需要額外的空間保存歸並的結果。

[Leetcode] Merge Sorted Array