/*********************************************************************
  C201 Computer Programming II
  Fall 2006
  Dana Vrajitoru &

  The data structure storing linked lists.

**********************************************************************/

#ifndef LIST_STR_H
#define LIST_STR_H

#include <string>
using namespace std;

struct Node {
  string word;
  Node *next;
};

typedef Node * Node_ptr;

// List traversal function. It prints all the elements of the list.
void Output_list(Node_ptr front);

// Returns the number of nodes in the list.
int Count_nodes(Node_ptr front);

// Inserts a new node at the front of the list. The front is a
// reference parameter because the new node becomes the front of the
// list.
void Insert_front(Node_ptr &front, string s);

// Removes the front node of the list. If the list is empty, it
// returns false.
bool Remove_front(Node_ptr &front);

// Deletes the entire list. It must also make the pointer front NULL.
void Delete_list(Node_ptr &front);

// Returns a pointer to the last node in the list.
Node_ptr Last_node(Node_ptr front);

// Searches for a particular string in the list. If the string is
// there, it returns a pointer to the node that contains it. If not,
// it return NULL.
Node_ptr Search(Node_ptr front, string s);

//****************** Homework functions ******************

// Insert the string as a new node at the back of the list.
void Insert_back(Node_ptr &front, string s);

// Returns a string obtained by the concatenation of the words in all
// the nodes of the list in order and separated by spaces.
string Concatenate(Node_ptr front);

// Returns a pointer to the node number i in the list, where the first
// node is at position 0. If the list has less than i+1 nodes, it
// returns NULL.
Node_ptr Access_index(Node_ptr front, int i);

// Converts the first letter of every word in the list to uppercase.
void Toupper_all(Node_ptr front);

// Converts the first letter of every word in the list to lowercase.
void Tolower_all(Node_ptr front);

// Reverses the list. It will most likely create a new list containing
// the same nodes as the list starting from front but in reverse
// order, then delete the old list and store the address of the first
// element of the new list in the pointer front.
void Reverse_list(Node_ptr &front);

#endif