const指针 防止指针指向的内容被修改
#include<iostream>
#include<string>
using namespace std;
struct Elephant{
string name;
Elephant* next;
};
void print_elephants(const Elephant* ptr);
Elephant* get_elephants();
void free_list(const Elephant* ptr);
int main()
{
Elephant* start;
start = get_elephants();
print_elephants(start);
free_list(start);
return 0;
}
Elephant* get_elephants(){
Elephant *current, *first;
int response;
current=first=new Elephant;
cout<<"\nName: ";
cin>>current->name;
cout<<endl<<"add? 1=Yes 0=No"<<endl;
cin>>response;
while(response == 1)
{
current = current->next = new Elephant;
cout<<"\nName: ";
cin>>current->name;
cout<<endl<<"add? 1=Yes 0=No"<<endl;
cin>>response;
}
current->next = 0;
return first;
}
void print_elephants(const Elephant* ptr)
{
while(ptr)
{
cout<<ptr->name<<endl;
ptr = ptr->next;
}
}
void free_list(const Elephant* ptr)
{
const Elephant* temp_ptr;
while(ptr)
{
temp_ptr = ptr->next;
delete ptr;
ptr= temp_ptr;
}
}