动态内存-动态数组
习题12.23
//连接字符串到动态数组
char *c = new char[20]();
char a[] = "hello ";
char b[] = "world";
strcopy(c, a);
strcopy(c+strlen(a), b);
cout<<c<<endl;
// 连接string到动态数组
char *c = new char[20]();
string a = "hello ";
string b = "world";
size_t idx = 0;
for(const auto &v : a)
c[idx++] = v;
for(const auto &v : b)
c[idx++] = v;
cout<<v<<endl;