struct默认成员为public的，class默认成员为private的，此外并没有什么区别
所以用一个结构体给另一个结构体赋值时，一般结构体里如果没有定义赋值运算符，则会像类那样使用默认赋值运算符或默认拷贝构造函数。
1 #include <iostream> 2 3 using namespace std; 4 5 struct xiaomao 6 { 7 int a; 8 float b; 9 int c[3]; 10 }; 11 12 struct damao 13 { 14 int a; 15 float b; 16 int *c; 17 }; 18 19 20 int main() 21 { 22 xiaomao aa = {1,2.0,{3,4,5}}; 23 cout << "aa" << endl; 24 cout << aa.a << endl; 25 cout << aa.b << endl; 26 cout << aa.c[0] << " " << aa.c[1] << " " << aa.c[2] << endl; 27 xiaomao bb = aa; 28 cout << "bb" << endl; 29 cout << bb.a << endl; 30 cout << bb.b << endl; 31 cout << bb.c[0] << " " << bb.c[1] << " " << bb.c[2] << endl; 32 bb.c[0] = 666; 33 cout << "after change: bb.c[0]:" << bb.c[0] << " " << "aa.c[0]:" << aa.c[0] << endl; 34 damao cc; 35 cc.a = 12; 36 cc.b = 13.0; 37 cc.c = new int[2]; 38 cc.c[0] = 5; 39 cc.c[1] = 6; 40 cout << "cc" << endl; 41 cout << cc.a << endl; 42 cout << cc.b << endl; 43 cout << cc.c[0] << " " << cc.c[1] << endl; 44 damao dd = cc; 45 cout << "dd" << endl; 46 cout << dd.a << endl; 47 cout << dd.b << endl; 48 cout << dd.c[0] << " " << dd.c[1] << endl; 49 50 dd.c[0] = 666; 51 cout << "after change: dd.c[0]:" << dd.c[0] << " " << "cc.c[0]:" << cc.c[0] << endl; 52 53 return 0; 54 }
运行结果：
aa
1
2
3 4 5
bb
1
2
3 4 5
after change: bb.c[0]:666 aa.c[0]:3
cc
12
13
5 6
dd
12
13
5 6
after change: dd.c[0]:666 cc.c[0]:666