c++11 - C++ linked list crashed -

i new on data structure. trying write linked list string , display list screen. crash @ node *p = create("i "); warning of access violation writing location. here code, don't know how fix it. please help. thank much.

#include <iostream> #include <cstdlib> #include <string>  using namespace std;  struct node {     string data;     node *prev, *next; };  node* create (string value) {     node *temp = (node*)malloc(sizeof(node));     if (null==temp) return null;      temp->data=value;     temp->next=null;     temp->prev=null;     return temp; }  void addhead (node* head, string value) {     node *temp = new node;     temp->data=value;     temp->next=head;     head->prev=temp;     head = temp;     temp->prev = null; }  void addtail (node* head, string value) {     node* s = new node;     node* temp = new node;     s=head;     while (s->next!=null)         s = s->next;     s->next = temp;     temp->prev = s; }  void display (node* head) {     if (head==null) return;     else     {         cout << head->data << " ";         display (head->next);     } }  int main() {     node *p = create("i ");     addtail(p, "want ");     addtail(p, "cookies ");      display(p);      return 0; }  

you need create node using new, not malloc, in create function. using malloc, constructor node not called, , assignment data access uninitialized string object.