#include <algorithm>
class Solution {
public:
    void merge(int A[], int m, int B[], int n) {
        
        for(int i=m; i<n+m; ++i)
            A[i] = B[i-m];

        // stable_sort() 还得引用才行,不然会报错
        stable_sort(&A[0], &A[n+m]);
    }
};