#include
#include
using namespace std;
// define default capacity of the queue
#define SIZE 10
// Class for queue
class queue {
int *arr; // array to store queue elements
int capacity; // maximum capacity of the queue
int front; // front points to front element in the queue (if any)
int rear; // rear points to last element in the queue
int count; // current size of the queue
public: // Ignore CPPLintBear
queue(int size = SIZE); // constructor
void dequeue();
void enqueue(int x);
int peek();
int size();
bool isEmpty();
bool isFull();
};
// Constructor to initialize queue
queue::queue(int size) {
arr = new int[size];
capacity = size;
front = 0;
rear = -1;
count = 0;
}
// Utility function to remove front element from the queue
void queue::dequeue() {
// check for queue underflow
if (isEmpty()) {
cout << "UnderFlow\nProgram Terminated\n";
exit(EXIT_FAILURE);
}
cout << "Removing " << arr[front] << '\n';
front = (front + 1) % capacity;
count--;
}
// Utility function to add an item to the queue
void queue::enqueue(int item) {
// check for queue overflow
if (isFull()) {
cout << "OverFlow\nProgram Terminated\n";
exit(EXIT_FAILURE);
}
cout << "Inserting " << item << '\n';
rear = (rear + 1) % capacity;
arr[rear] = item;
count++;
}
// Utility function to return front element in the queue
int queue::peek() {
if (isEmpty()) {
cout << "UnderFlow\nProgram Terminated\n";
exit(EXIT_FAILURE);
}
return arr[front];
}
// Utility function to return the size of the queue
int queue::size() {
return count;
}
// Utility function to check if the queue is empty or not
bool queue::isEmpty() {
return (size() == 0);
}
// Utility function to check if the queue is full or not
bool queue::isFull() {
return (size() == capacity);
}
// main function
int main() {
// create a queue of capacity 5
queue q(5);
q.enqueue(1);
q.enqueue(2);
q.enqueue(3);
cout << "Front element is: " << q.peek() << endl;
q.dequeue();
q.enqueue(4);
cout << "Queue size is " << q.size() << endl;
q.dequeue();
q.dequeue();
q.dequeue();
if (q.isEmpty())
cout << "Queue Is Empty\n";
else
cout << "Queue Is Not Empty\n";
return 0;
}