Инициализация членов структуры

#include <iostream>
struct Pizza
{
    char name[20];
    double diametr;
    double weidth;
};
 
int main()
{
    using namespace std;
    Pizza* ps = new Pizza;
    cout << "Enter the pizza diametr: ";
    cin >> ps->diametr;
    cout << "\nEnter the pizza name: ";
    cin.get(ps->name,20).get();
    cout << "\nEnter the pizza weidth: ";
    cin >> ps->weidth;
 
    cout << ps->name << ", " << ps->diametr << ", " << ps->weidth << '.';
    
    delete ps;
    
    cin.get();
    return 0;
}

struct MyElement {
  MyElement * next;
  MyElement * prev;
  string data;
};
 
class MyList {
 public:
  explicit MyList(){
    MyElement *head = new ListNode;
    head->next = 0;
    head->prev = 0;
    head->data = "";
    MyElement *tail = new ListNode;
    tail->next = 0;
    tail->prev = 0;
    tail->data = "";
    count      = 0;
  }
  void push_back(string indata){
    if(count == 0) {
      head->next = 0;
      head->data = indata;
      tail = head;
    } else {
      tail->data = indata;
      tail->prev = tail;
      tail->next = 0;
    }
   count++;
  }
 private:
  MyElement * head;
  MyElement * tail;
  int count;
};
 
int main(){
  MyList* list = new MyList;
  string buf[4] = {"this","prog","must","work!"};
  for(int i=0;i<4;i++) list->push_back(buf[i]);
  return 0;
}