代码

#include<cstdlib>
#include<new>
class a{
public:
    a(int x=0):n(x){}
    int n;
};
int plus(int x, int y){
    void *p=malloc(sizeof(a)),*pp=malloc(sizeof(a));
    a *ap=new(p) a(x),*bp=new(pp) a(y);
    return ap->n+bp->n;
}

评测结果