queue.java

public class Main{
    
    
    static class Queue{
       static int arr[];
       static int size;
       static int rear;
        
        Queue(int n){
            arr = new int[n];
            size = n;
            rear = -1;
            
        }
        
    public static boolean isEmpty(){
        return rear == -1; 
    }
    
    //add 
    public static void add(int data){
        if(rear== size-1){
            
            System.out.print("Oueue is empty");
            return;
        }
        
        rear = rear+1;
        arr[rear] = data;
        
    }
    
    //remove 
    public static int remove(){
        if(isEmpty()){
            System.out.println("Queue is empty");
            return -1;
        }
        
        int front = arr[0];
        for(int i =0; i<rear; i++){
            arr[i]= arr[i+1];
        }
        rear = rear -1;
        return front;
    }
        
    //peek 
    public static int peek(){
        if(isEmpty()){
            System.out.println("Queue is empty");
            return -1;
            
        }
        
        return arr[0];
    }
        
        
        
    }
    
    
    public static void main(String args[]){
        Queue q = new Queue(5);
        q.add(1);
        q.add(2);
        q.add(3);
        
        while(!q.isEmpty()){
            System.out.println(q.peek());
            q.remove();
        }
        
    }
    
    
}