88 合并两个有序数组

https://leetcode.cn/leetbook/read/top-interview-questions-easy/xnumcr/

https://leetcode.cn/problems/merge-sorted-array/description/

cost: 18m06s

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

• 时间复杂度：O(m+n)
• 空间复杂度：O(1)