1 #include "iostream"
2 using namespace std;
3
4 class A{};
5 class A2{char d,e;};
6 struct B{};
7 struct C{char b,c;};
8 struct D{int x,y;};
9
10 int main()
11 {
12
13 cout << "sizeof(A) = " << sizeof(A) <<endl; //1 空类的长度就是1
14 cout << "sizeof(A2) = " << sizeof(A2) <<endl; //2
15
16 A *p1 = new A();
17 A p2;
18 A *p3;
19
20 cout << "sizeof(p1) = " << sizeof(p1) << endl; //8
21 cout << "sizeof(p2) = " << sizeof(p2) << endl; //1
22 cout << "sizeof(p3) = " << sizeof(p3) << endl; //8
23
24 cout << "sizeof(B) = " << sizeof(B) <<endl;//1
25 cout << "sizeof(C) = " << sizeof(C) <<endl;//2
26 cout << "sizeof(D) = " << sizeof(D) <<endl;//8
27
28
29
30 cout << "hello world" << endl;
31 return 0;
32 }
