Stack implementation

Data Structures/03 Stack/Stack.cpp

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+#include <iostream>
+#include <cstdlib>
+using namespace std;
+
+// define size capacity of the stack
+#define SIZE 10
+
+// Class for stack
+class stack
+{
+	int *arr;
+	int top;
+	int capacity;
+
+public:
+	// constructor
+	stack(int size = SIZE);
+	// destructor
+	~stack();   				
+
+	void push(int);
+	int pop();
+	int peek();
+
+	int size();
+	bool isEmpty();
+	bool isFull();
+};
+
+// Constructor to initialize stack
+stack::stack(int size)
+{
+	arr = new int[size];
+	capacity = size;
+	top = -1;
+}
+
+// Destructor to free memory allocated to the stack
+stack::~stack()
+{
+	delete arr;
+}
+
+//Function to add an element x in the stack
+void stack::push(int x)
+{
+	if (isFull())
+	{
+		cout << "OverFlow\nProgram Terminated\n";
+		exit(EXIT_FAILURE);
+	}
+
+	cout << "Inserting " << x << endl;
+	arr[++top] = x;
+}
+
+//Function to pop top element from the stack
+int stack::pop()
+{
+	// check for stack underflow
+	if (isEmpty())
+	{
+		cout << "UnderFlow\nProgram Terminated\n";
+		exit(EXIT_FAILURE);
+	}
+
+	cout << "Removing " << peek() << endl;
+
+	// decrease stack size by 1 and return the popped element if required
+	return arr[top--];
+}
+
+//Function to return top element in a stack
+int stack::peek()
+{
+	if (!isEmpty())
+		return arr[top];
+	else
+		exit(EXIT_FAILURE);
+}
+
+//Function to return the size of the stack
+int stack::size()
+{
+	return top + 1;
+}
+
+//Function to check if the stack is empty or not
+bool stack::isEmpty()
+{
+	return top == -1;	// or return size() == 0;
+}
+
+//Function to check if the stack is full or not
+bool stack::isFull()
+{
+	return top == capacity - 1;	// or return size() == capacity;
+}
+
+// Driver unction
+int main()
+{
+	stack pt(3);
+
+	pt.push(1);
+	pt.push(2);
+
+	pt.pop();
+	pt.pop();
+
+	pt.push(3);
+
+	cout << "Top element is: " << pt.peek() << endl;
+
+	cout << "Stack size is " << pt.size() << endl;
+
+	pt.pop();
+
+	if (pt.isEmpty())
+		cout << "Stack Is Empty\n";
+	else
+		cout << "Stack Is Not Empty\n";
+
+	return 0;
+}