Initial commit

P1/VariableLinkedList.cpp

@@ -0,0 +1,88 @@
+#include "VariableLinkedList.h"
+
+using namespace std;
+
+VariableLinkedList::VariableLinkedList(int cap)
+{
+    this->maxCount = cap;
+    this->count = 0;
+    this->head = nullptr;
+}
+
+VariableLinkedList::~VariableLinkedList()
+{
+    if (head != nullptr)
+        head->DestroyAll();
+}
+
+/// @brief Insert a variable into the head of the linked list
+/// @param name The name of the variable to insert
+/// @param value The double value to initialize the variable with
+/// @return True if the variable was added, false otherwise
+bool VariableLinkedList::insert(string name, double value)
+{
+    // Ensure there is space
+    if (count == maxCount)
+        return false;
+
+    // Ensure the variable does not exist
+    VariableNode *s = this->search(name);
+    if (s != nullptr)
+        return false;
+
+    // Insert a new VariableNode into the head.
+    head = new VariableNode(name, value, head);
+    
+    count++;
+    return true;
+}
+
+/// @brief Remove the variable with name from the linked list
+/// @param name The name of the variable to remove
+/// @return True if removed, false otherwise
+bool VariableLinkedList::remove(string name)
+{
+    // Root node must be handled in a seperate case
+    if (head != nullptr && head->getName() == name)
+    {
+        VariableNode *temp = head->getNext();
+        delete head;
+        head = temp;
+        count --;
+        return true;
+    }
+
+    // Search for the node before the one we want to remove.
+    VariableNode *currentIndex = this->head;
+    while (currentIndex != nullptr && currentIndex->getNext() != nullptr && 
+           currentIndex->getNext()->getName() != name)
+        currentIndex = currentIndex->getNext();
+
+    // currentIndex will be null if the index does not exist.
+    if (currentIndex == nullptr || currentIndex->getNext() == nullptr)
+        return false;
+
+    VariableNode *temp = currentIndex->getNext()->getNext();
+    delete currentIndex->getNext();
+    count--;
+    currentIndex->setNext(temp);
+    return true;
+}
+
+/// @brief Search for the variable with the given name
+/// @param name The name of the variable to search for
+/// @return A pointer to a valid VariableNode if the node exists, nullptr otherwise
+VariableNode *VariableLinkedList::search(string name)
+{
+    VariableNode *currentIndex = this->head;
+    while (currentIndex != nullptr)
+    {
+        if (currentIndex->getName() == name)
+        {
+            return currentIndex;
+        }
+        currentIndex = currentIndex->getNext();
+    }
+
+    return nullptr;
+}