[leetcode] Merge Sorted Array

From : https://leetcode.com/problems/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 nums1and nums2 are m and n respectively.

class Solution {
public:
void merge(vector<int>& nums1, int m, vector<int>& nums2, int n) {
int index = m+n-1, idx1 = m-1, idx2 = n-1;
while(idx2 >= 0 && idx1 >= 0) {
if(nums2[idx2] > nums1[idx1]) {
nums1[index--] = nums2[idx2];
idx2--;
} else {
nums1[index--] = nums1[idx1];
idx1--;
}
}
while(idx1>=0) {
nums1[index--] = nums1[idx1--];
}
while(idx2>=0) {
nums1[index--] = nums2[idx2--];
}
}
};