单项选择题

有如下程序:
#include <iostream.h>
using namespace std;
class Stack

public:
Stack (unsigned n=10):size (n) rep_=new int [size]; top=0;
Stack (stack&s: size (s.size)

rep_new int[size];
for (int i=0;i<size;i++
rip_[i]-s.rep_[i];
top=s.top;

~Stack() delete[]rep_;
void poush(int

A.rep_[topj=a; top++;
&nb