[leetcode]Merge Sorted Array

Given two sorted integer arrays A and B, merge B into A as one sorted array.
Note:
You may assume that A has enough space to hold additional elements from B. The number of elements initialized in A and B are m and n respectively.

归并排序。

class Solution {
public:
    void merge(int A[], int m, int B[], int n) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int tag1 = m-1,tag2 = n-1;
        for(int i =  m+n-1;i >= 0 ; i--)
        {
            if(tag1 == -1 || tag2 == -1)
            {
                if(tag1 == -1)
                {
                    A[i] = B[tag2];
                    tag2--;                   
                }
                else
                {
                    A[i] = A[tag1];
                    tag1--;                    
                }
            }
            else
            {
                if(A[tag1] >= B[tag2])
                {
                    A[i] = A[tag1];
                    tag1--;
                }
                else
                {
                    A[i] = B[tag2];
                    tag2--;
                }
            }
        }
    }
};