小编Ida*_*yev的帖子

我得到了这个代码：

1 #include <iostream>
2 using namespace std;
3
4 class B {
5 private:
6      int n;
7 public:
8      B(int x) : n(x) {}
9      B operator +(B& b) {
10         return B(n+b.n);
11     }
12     friend ostream& operator <<(ostream &out, const B& b) {
13         out << "B: " << b.n;
14         return out;
15     }
16     bool operator <(const B& rhs) const{
17         return n < rhs.n;
18     }
19 };
20
21 B smaller (const …