1 struct huge_data{
 2     char *content;
 3     unsigned sz;
 4     huge_data():content(0),sz(0){
 5         cout<<this<<"->huge_data()"<<endl;
 6     }
 7 
 8     huge_data(unsigned sz):content(new char[sz]),sz(sz){
 9         cout<<this<<"->huge_data("<<sz<<")"<<endl;
10     }
11 
12     huge_data(huge_data const &h):content(new char[h.sz]),sz(h.sz){
13         copy(h.content,h.content+sz,content);
14         cout<<this<<"->huge_data("<<&h<<")"<<endl;
15     }
16 
17     huge_data &operator=(huge_data const &h){
18         if(&h == this) return *this;
19         if(content) delete[] content;
20 
21         content = new char[h.sz];
22         copy(h.content,h.content+sz,content);
23         sz = h.sz;
24         cout<<this<<"->operator=("<<&h<<")"<<endl;
25         return *this;
26     }
27     ~huge_data(){
28         if(content){
29             delete[] content;
30         }
31     }
32 };
33 
34 huge_data prepare_data(unsigned sz){
35     huge_data h(sz);
36     memset(h.content,'a',sizeof(char)*sz);
37     return h;
38 }
39 
40 class BFS{
41 public:
42     void test(){
43         cout<<"begin"<<endl;
44         huge_data a;
45         a = prepare_data(1024);
46 
47 
48         cout<<"end"<<endl;
49     }
50 };

begin
0x7ffecce0c7f0->huge_data()
0x7ffecce0c7b0->huge_data(1024)
0x7ffecce0c800->huge_data(0x7ffecce0c7b0)
0x7ffecce0c7f0->operator=(0x7ffecce0c800)
end

Process returned 0 (0x0)   execution time : 0.003 s
Press ENTER to continue.

begin
0x7ffd15fa0db0->huge_data()
0x7ffd15fa0dc0->huge_data(1024)
0x7ffd15fa0db0->operator=(0x7ffd15fa0dc0)
end