linear_structures_example.C

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/*
                          Aleph_w
 
  Data structures & Algorithms
  version 2.0.0b
  https://github.com/lrleon/Aleph-w
 
  This file is part of Aleph-w library
 
  Copyright (c) 2002-2026 Leandro Rabindranath Leon
 
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
 
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
 
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/
 
 
#include <iostream>
#include <string>
#include <tpl_dynListStack.H>
#include <tpl_dynListQueue.H>
#include <tpl_dynArray.H>
#include <tpl_dynList.H>
#include <tpl_dynDlist.H>
#include <tpl_arrayStack.H>
#include <tpl_arrayQueue.H>
 
using namespace std;
using namespace Aleph;
 
// =============================================================================
// Example 1: Stack (LIFO)
// =============================================================================
 
void demo_stack()
{
  cout << "\n";
  cout << "╔══════════════════════════════════════════════════════════════════╗\n";
  cout << "║      EXAMPLE 1: Stack (LIFO - Last In First Out)                 ║\n";
  cout << "╚══════════════════════════════════════════════════════════════════╝\n\n";
 
  cout << "Stack follows LIFO principle: last element pushed is first popped.\n\n";
 
  // Dynamic stack (unlimited size)
  DynListStack<string> stack;
 
  cout << "--- DynListStack operations ---\n\n";
 
  // Push elements
  cout << "Pushing: Apple, Banana, Cherry, Date\n";
  stack.push("Apple");
  stack.push("Banana");
  stack.push("Cherry");
  stack.push("Date");
 
  cout << "Stack size: " << stack.size() << "\n";
  cout << "Top element: " << stack.top() << "\n\n";
 
  // Pop elements
  cout << "Popping elements (LIFO order):\n";
  while (!stack.is_empty())
    cout << "  Pop: " << stack.pop() << "\n";
 
  cout << "\n--- Practical application: Balanced parentheses ---\n\n";
 
  auto check_balanced = [](const string& expr) {
    DynListStack<char> s;
    for (char c : expr) {
      if (c == '(' || c == '[' || c == '{')
        s.push(c);
      else if (c == ')' || c == ']' || c == '}') {
        if (s.is_empty()) return false;
        char top = s.pop();
        if ((c == ')' && top != '(') ||
            (c == ']' && top != '[') ||
            (c == '}' && top != '{'))
          return false;
      }
    }
    return s.is_empty();
  };
 
  auto test_expr = [&](const string& expr) {
    cout << "  \"" << expr << "\" → " 
         << (check_balanced(expr) ? "BALANCED" : "UNBALANCED") << "\n";
  };
 
  test_expr("((a+b)*c)");
  test_expr("{[a+(b*c)]}");
  test_expr("((a+b)");
  test_expr("([a+b)]");
}
 
// =============================================================================
// Example 2: Queue (FIFO)
// =============================================================================
 
void demo_queue()
{
  cout << "\n";
  cout << "╔══════════════════════════════════════════════════════════════════╗\n";
  cout << "║      EXAMPLE 2: Queue (FIFO - First In First Out)                ║\n";
  cout << "╚══════════════════════════════════════════════════════════════════╝\n\n";
 
  cout << "Queue follows FIFO principle: first element added is first removed.\n\n";
 
  DynListQueue<string> queue;
 
  cout << "--- DynListQueue operations ---\n\n";
 
  // Enqueue elements
  cout << "Enqueueing: Task1, Task2, Task3, Task4\n";
  queue.put("Task1");
  queue.put("Task2");
  queue.put("Task3");
  queue.put("Task4");
 
  cout << "Queue size: " << queue.size() << "\n";
  cout << "Front element: " << queue.front() << "\n";
  cout << "Rear element: " << queue.rear() << "\n\n";
 
  // Dequeue elements
  cout << "Dequeueing elements (FIFO order):\n";
  while (!queue.is_empty())
    cout << "  Dequeue: " << queue.get() << "\n";
 
  cout << "\n--- Practical application: Print job scheduler ---\n\n";
 
  struct PrintJob {
    string name;
    int pages;
  };
 
  DynListQueue<PrintJob> printer;
 
  // Add print jobs
  printer.put({"Report.pdf", 10});
  printer.put({"Photo.jpg", 1});
  printer.put({"Manual.pdf", 50});
  printer.put({"Letter.doc", 2});
 
  cout << "Print queue:\n";
  int total_pages = 0;
  while (!printer.is_empty()) {
    PrintJob job = printer.get();
    cout << "  Printing: " << job.name << " (" << job.pages << " pages)\n";
    total_pages += job.pages;
  }
  cout << "Total pages printed: " << total_pages << "\n";
}
 
// =============================================================================
// Example 3: Dynamic Array
// =============================================================================
 
void demo_dynarray()
{
  cout << "\n";
  cout << "╔══════════════════════════════════════════════════════════════════╗\n";
  cout << "║      EXAMPLE 3: DynArray (Resizable Array)                       ║\n";
  cout << "╚══════════════════════════════════════════════════════════════════╝\n\n";
 
  cout << "DynArray provides O(1) random access with dynamic resizing.\n\n";
 
  DynArray<int> arr;
 
  cout << "--- Basic operations ---\n\n";
 
  // Append elements
  cout << "Appending: 10, 20, 30, 40, 50\n";
  arr.append(10);
  arr.append(20);
  arr.append(30);
  arr.append(40);
  arr.append(50);
 
  cout << "Size: " << arr.size() << "\n";
  cout << "Elements: ";
  for (size_t i = 0; i < arr.size(); ++i)
    cout << arr(i) << " ";
  cout << "\n\n";
 
  // Random access
  cout << "Random access:\n";
  cout << "  arr(0) = " << arr(0) << "\n";
  cout << "  arr(2) = " << arr(2) << "\n";
  cout << "  arr(4) = " << arr(4) << "\n\n";
 
  // Modify element
  cout << "Modifying arr(2) = 300\n";
  arr(2) = 300;
  cout << "Elements: ";
  for (size_t i = 0; i < arr.size(); ++i)
    cout << arr(i) << " ";
  cout << "\n\n";
 
  cout << "--- Functional operations ---\n\n";
 
  DynArray<int> numbers;
  for (int i = 1; i <= 10; ++i)
    numbers.append(i);
 
  cout << "Original: ";
  numbers.for_each([](int x) { cout << x << " "; });
  cout << "\n";
 
  // Filter even numbers
  auto evens = numbers.filter([](int x) { return x % 2 == 0; });
  cout << "Evens:    ";
  evens.for_each([](int x) { cout << x << " "; });
  cout << "\n";
 
  // Map: square each number
  auto squared = numbers.maps<int>([](int x) { return x * x; });
  cout << "Squared:  ";
  squared.for_each([](int x) { cout << x << " "; });
  cout << "\n";
 
  // Fold: sum all numbers
  int sum = numbers.foldl(0, [](int acc, int x) { return acc + x; });
  cout << "Sum:      " << sum << "\n";
}
 
// =============================================================================
// Example 4: Dynamic Lists
// =============================================================================
 
void demo_dynlist()
{
  cout << "\n";
  cout << "╔══════════════════════════════════════════════════════════════════╗\n";
  cout << "║      EXAMPLE 4: DynList and DynDlist (Linked Lists)              ║\n";
  cout << "╚══════════════════════════════════════════════════════════════════╝\n\n";
 
  cout << "Linked lists allow O(1) insertion/deletion at any known position.\n\n";
 
  // Singly linked list
  cout << "--- DynList (singly linked) ---\n\n";
 
  DynList<int> slist;
 
  // Insert at front (O(1))
  cout << "Inserting at front: 3, 2, 1\n";
  slist.insert(3);
  slist.insert(2);
  slist.insert(1);
 
  // Append at end
  cout << "Appending at end: 4, 5\n";
  slist.append(4);
  slist.append(5);
 
  cout << "List: ";
  slist.for_each([](int x) { cout << x << " "; });
  cout << "\n";
  cout << "Size: " << slist.size() << "\n\n";
 
  // Doubly linked list
  cout << "--- DynDlist (doubly linked) ---\n\n";
 
  DynDlist<string> dlist;
 
  cout << "Inserting: First, Second, Third\n";
  dlist.append("First");
  dlist.append("Second");
  dlist.append("Third");
 
  cout << "Forward:  ";
  dlist.for_each([](const string& s) { cout << s << " "; });
  cout << "\n";
 
  // Remove from front and back
  cout << "\nRemoving first: " << dlist.remove_first() << "\n";
  cout << "Removing last: " << dlist.remove_last() << "\n";
 
  cout << "Remaining: ";
  dlist.for_each([](const string& s) { cout << s << " "; });
  cout << "\n";
}
 
// =============================================================================
// Example 5: Comparison of Stack vs Queue
// =============================================================================
 
void demo_comparison()
{
  cout << "\n";
  cout << "╔══════════════════════════════════════════════════════════════════╗\n";
  cout << "║      EXAMPLE 5: Stack vs Queue Comparison                        ║\n";
  cout << "╚══════════════════════════════════════════════════════════════════╝\n\n";
 
  DynListStack<int> stack;
  DynListQueue<int> queue;
 
  // Add same elements to both
  cout << "Adding elements 1, 2, 3, 4, 5 to both structures:\n\n";
  for (int i = 1; i <= 5; ++i) {
    stack.push(i);
    queue.put(i);
  }
 
  // Remove and compare order
  cout << "Removal order:\n";
  cout << "  Stack (LIFO): ";
  while (!stack.is_empty())
    cout << stack.pop() << " ";
  cout << "\n";
 
  cout << "  Queue (FIFO): ";
  while (!queue.is_empty())
    cout << queue.get() << " ";
  cout << "\n";
 
  cout << "\nUse Stack for: undo/redo, recursion, backtracking\n";
  cout << "Use Queue for: scheduling, BFS, buffering\n";
}
 
// =============================================================================
// Main
// =============================================================================
 
int main()
{
  cout << "\n";
  cout << "╔══════════════════════════════════════════════════════════════════╗\n";
  cout << "║         Linear Data Structures in Aleph-w Library                ║\n";
  cout << "║                                                                  ║\n";
  cout << "║     Aleph-w Library - https://github.com/lrleon/Aleph-w          ║\n";
  cout << "╚══════════════════════════════════════════════════════════════════╝\n";
 
  demo_stack();
  demo_queue();
  demo_dynarray();
  demo_dynlist();
  demo_comparison();
 
  cout << "\n";
  cout << "╔══════════════════════════════════════════════════════════════════╗\n";
  cout << "║                         Summary                                  ║\n";
  cout << "╠══════════════════════════════════════════════════════════════════╣\n";
  cout << "║  DynListStack:  Dynamic LIFO stack (linked list based)          ║\n";
  cout << "║  DynListQueue:  Dynamic FIFO queue (circular list based)        ║\n";
  cout << "║  DynArray:      Resizable array with O(1) access                ║\n";
  cout << "║  DynList:       Singly linked list                              ║\n";
  cout << "║  DynDlist:      Doubly linked list                              ║\n";
  cout << "║                                                                  ║\n";
  cout << "║  All support functional operations: map, filter, fold, for_each ║\n";
  cout << "╚══════════════════════════════════════════════════════════════════╝\n\n";
 
  return 0;
}