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.
从后往前扫一遍
class Solution { public: void merge(vector<int>& nums1, int m, vector<int>& nums2, int n) { int index = n + m - 1; int i = m - 1; int j = n - 1; while (i >= 0 && j >= 0) { if (nums1[i] > nums2[j]) nums1[index--] = nums1[i--]; else nums1[index--] = nums2[j--]; } while (j >= 0) { nums1[index--] = nums2[j--]; } } };