c++ List class as Student type -

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i trying use class student , declare list type. can pushback without changing list.h or node.h how can print data in list2? given print() function within list..h not work :(

node.h

#ifndef node_h #define node_h #include <string> #include <iostream> using namespace std; template <typename t> class node { private:   t data;   node<t>* next; public:   node(t);   virtual ~node(); // base class destructor must virtual    template <typename u> friend class list; }; template <typename t> node<t>::node(t d) {   data = d;   next = null; } template <typename t> node<t>::~node() { } #endif  /* strnode_h */

list.h

#ifndef list_h #define list_h #include "node.h"  // singly linked list template <typename t> class list { private:   node<t>* head; // pointer first node   node<t>* tail; // pointer last node   int count;  // number of nodes in list public:    class outofrangeexception{ }; // empty inner class exception handling    list();    virtual ~list();    void push_back(t item);    void insert(int index, t item);    void remove(int index);    int indexof(t item);    t get(int position); // outofrangeexception generated    bool isempty();    int size();    void print();   };  template <typename t>  list<t>::list() {  head = tail = null;   count = 0;  }  template <typename t>  list<t>::~list() {  node<t>* discard;  while (head != 0) {  discard = head;  head = head->next;  delete discard;  }  }    // append item @ end of strlist  template <typename t>  void list<t>::push_back(t item) {  try {  node<t>* newnode = new node<t>(item);  if (head == 0) {   head = tail = newnode;    } else {    tail->next = newnode;    tail = newnode;   }    ++count;   } catch (bad_alloc &e) {    cout << "memory allocation exception: " << e.what() << endl;  exit(1);  }  }   // insert item @ specified index  template <typename t>  void list<t>::insert(int index, t item) {  try {  if (index < 0 || index > count) // push_back() if index == count   throw outofrangeexception();    node<t>* newnode = new node<t>(item);   if (head == 0) { // empty   head = tail = newnode;   } else if (index == 0) { // @ start   newnode->next = head;   head = newnode;   } else if (index == count) { // @ end   tail->next = newnode;   tail = newnode;   } else { // insert in middle   node<t>* prevnode;   node<t>* currnode = head;   (int = 0; < index; i++) {     prevnode = currnode;     currnode = currnode->next;   }   // insert between 'prevnode' , 'currnode'   prevnode->next = newnode;   newnode->next = currnode;  }   ++count;   } catch (bad_alloc &e) {  cout << "memory allocation exception: " << e.what() << endl;   exit(1);  }  }   // strlist empty?   template <typename t>   bool list<t>::isempty() {   return count == 0;    }    // remove item @ specified index   template <typename t>   void list<t>::remove(int index) {    if (index < 0 || index >= count)    throw outofrangeexception();     if (index == 0) { // @ start     node<t>* discard = head;     head = head->next;     delete discard;      } else {     node<t>* prevnode;     node<t>* currnode = head;     (int = 0; < index; i++) {      prevnode = currnode;      currnode = currnode->next;     }    // remove 'currnode'     prevnode->next = currnode->next; // bypass      delete currnode;      if (index == count - 1) // last node removed. update 'tail'     tail = prevnode;     }     --count;    if (count == 0)    tail = null;    }   // retrieve item @ given position of strlist. position starts 0.   // throws outofrangeexception if invalid position value given.   template <typename t>  t list<t>::get(int position) {   if (position < 0 || position >= count)   throw outofrangeexception();      int loc = 0;      node<t>* curr = head;      while (loc < position) {     ++loc;    curr = curr->next;     }    return curr->data;    }    // requirement:   //   != operator of <class t>  used   template <typename t>  int list<t>::indexof(t item) {    if (head == 0) {    return -1; // not found   } else {   int index = 0;    node<t>* currnode = head;     while (currnode->data != item && currnode != null) {    currnode = currnode->next;      ++index;   }    if (currnode == null) // not found thru end      return -1;   else     return index;  }  }    // number of nodes in strlist   template <typename t>   int list<t>::size() {    return count;   }   // requirement:  //   << operator <class t> used.   template <typename t>  void list<t>::print() {   cout << "*** strlist contents ***" << endl;    (int = 0; < count; i++) {    cout << << ": " << get(i) << endl;     }   }  #endif

student.h

#include "list.h"  class student {  private: string name; int id; public: student(); student(string a); virtual ~student(); friend ostream& operator<<(ostream &os, const student& p); bool operator!=(const student &p) const; bool operator==(const student &p) const; }; student::student() { } student::student(string a) { name = a;  }  student::~student() {  } ostream& operator<<(ostream &os, const student& p) { return os << p.name; }  bool student::operator==(const student &p) const {  // compare values, , return bool result. if (name == p.name)     return true; else return false; }  bool student::operator!=(const student &p) const { return !(*this == p);  }

main.cpp

 #include <iostream>  using namespace std;   #include "student.h"   int main() {    cout << "\n*** strlist test ***" << endl;   list<string> list;  list.push_back("zero");  list.push_back("one");  list.push_back("two");  list.push_back("three");  list.push_back("four");  list.push_back("five");  list.print();    list.insert(1, "inserted @ position 1");   list.insert(0, "inserted @ position 0");   list.insert(4, "inserted @ position 4");   list.print();    cout << "removing @ indexes 3, 0" << endl;   list.remove(3);   list.remove(0);  list.print();   list.insert(2, "inserted @ position 2");  list.print();     cout << "five @ index " << list.indexof("five") << endl;   cout << "two @ index " << list.indexof("two") << endl;     //test student class implementation   //  student<string> st1; //create new student ryan martin id of 1   list<student> list2;   student stu("ryan martin");    list2.push_back(stu);   //list2.print();   //list2.push_back("ryan");   //list2.printstudents(); //test student class stored , can          access   return 0;   }

the << operator must defined student class. quote list.h:

// requirement:  //   << operator <class t> used.   template <typename t>  void list<t>::print() {   cout << "*** strlist contents ***" << endl;    (int = 0; < count; i++) {    cout << << ": " << get(i) << endl;     }   }

so in student class, need implement operator<<(ostream &out);

do friend (friends fun!):

friend std::ostream& operator<< (std::ostream &out, const student &stu) {     return out << stu.name << " id: " << stu.id << std::endl; }

here reference: http://www.learncpp.com/cpp-tutorial/93-overloading-the-io-operators/


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