有如下程序： #nclude＜iostremn＞ using namespace std class Stack{ public: Stack(unsigned n=10:size(n){rep_=new int[size]top=O} Stack(Stack&s):size(s.size) { rep_=new int[size] for(int i=0i＜sizei++)rep_[i]=s.rep_[i] top=s.top } ～Stack(){delete[]rep_} void push(int a){rep_[top]=a top++} int opo(){--topreturn rep_[top]} bool is Empty()const{return top==O} pavate: int*rep_ unsigned size,top } int main() { Stack s1 for(int i=1i＜5i++) s1.push(i) Stack s2(s1) for(i=1i＜3i++) cout＜＜s2.pop()＜＜',' s2.push(6) s1.push(7) while(!s2.isEmpty()) cout＜＜s2.pop()＜＜',' return 0； } 执行上面程序的输出是