Question 2. Linked Lists [9]

The table below shows a program and the output we would see if we attempted to run it.
Identify why the segmentation fault occurs and provide an appropriate fix. (Only a one-line change is needed.) 
#include <iostream>
using namespace std;

class list {
   public:
     list();             // create an empty list
     ~list();            // delete all remaining nodes
     void insert(int v); // insert v at front of list
     void remove();      // remove/discard back list node 
     void print();       // display list contents
   private:
     struct node {
        int value;
        node *next;
     } *Lptr;  // Lptr tracks the front of the list
};

int main() {
   list L;
   L.insert(1);
   L.insert(2);
   L.print();
   L.remove();
   L.print();
}

void list::insert(int v) {
   node *n = new node();
   if (n != NULL) {
      n->value = v;
      n->next = Lptr;
      Lptr = n;
   }
}

list::list() {
   Lptr = NULL;
}

list::~list() {
   while (Lptr != NULL) remove();
}

void list::print() {
   node *n = Lptr;
   cout << "List contents: ";
   while (n != NULL) {
      cout << n->value;
      n = n->next;
      if (n != NULL) cout << ", ";
      else cout << "." << endl;
   }
}

void list::remove() {
   if (Lptr == NULL) return;
   if (Lptr->next == NULL) {
      delete Lptr;
      Lptr = NULL;
   }
   node *n = Lptr;
   node *prev = NULL;
   while (n->next != NULL) {
      prev = n;
      n = n->next;
   }
   delete n;
   prev->next = NULL;
}
// resulting output
List contents: 2, 1.
List contents: 2.
Segmentation fault