Question: you are expected to develop a simple version of the web browsers Go back one page, and Go forward one page functionality utilizing two stacks. These two stacks will be called as backward_stack and forward_stack. They will keep the web addresses that you visited previously.

In the application you will generate a menu as displayed in the sample run and allow user to select following functionalities; visit new webpage, go back one page, go forward one page. Do not forget that the webpage you currently are in may not have a previous page or a forward page. If that is the case, you must give appropriate error messages. Check the sample output thoroughly to understand the application functionality.

Important Note: Use LStack.h header file on the moodle web page, which is also attached to this homework notification. Do not change any functionality within the header file or upload your own header file. Your home-works will be graded only with the given header file.

Sample run:

The header file:

/* * LStack.h * * Created on: Nov 17, 2020 * Author: Ziya Karakaya * Desciption: * Stack class implemented using linked list notation * * Last update : Nov 25, 2020 * Version: v0.2 * Update Notes: * We changed the name Node to SNode in order to prevent redefinition error when used with other ADTs. * */

#ifndef STACK_H_ #define STACK_H_

#include #include using namespace std;

template struct SNode { T data; SNode *next; };

template class Stack { protected: SNode *top; //head becomes top. Items should be inserted from top. int cnt; public: //Constructor Stack() { top = NULL; //sets top initial value to NULL cnt = 0; } //Destructor ~Stack() { clear(); } bool isEmpty() { return top == NULL; } //There is no size limitation in Stack using LinkedList implementation. We do not need to check if the stack is full or not. T peek() { // you can name it as peek assert( !isEmpty() ); //if not empty return top->data;//return the value on the top } T pop(); void push(const T&); void clear(); int size(); };

//resets the stack to its initial state template void Stack::clear() { SNode *p; while (top != NULL) { p = top; top = top->next; delete p; } cnt = 0; }

//insert a new item to the top of stack template void Stack::push(const T &item) { SNode *newNode = new SNode; newNode->data = item; newNode->next = top; top = newNode; cnt++; }

//retrieve (remove and return) the top value template T Stack::pop() { SNode *p; //pointer to traverse T item; assert(!isEmpty()); //if the stack is empty terminate p = top; item = top->data; top = top->next; delete p; cnt--; return item; }

template int Stack:: size(){ return cnt; }

#endif /* STACK_H_ */

Sample Run: (Bold strings below are user inputs) Choose (N) ew page, go (B)ack one page, go (F) orward one page (0) uit: N Enter new page address: www.google.com You are currently visiting google. Choose (N) ew page, go (B)ack one page, go (F) orward one page (Q) uit: F Error! There is no Forward page. You are currently visiting google. Choose (N) ew page, go (B)ack one page, go (F) orward one page (Q) uit: N Enter new page address: www.instagram.com You are currently visiting instagram