package com.data.struct;

public class ArrayQueue {
  private int []data;
  private int head;
  private int tail;
  private boolean full;
  public ArrayQueue(int size){
    data=new int[size];
    head=0;
    tail=0;
  }
  public void enqueue(int d)throws Exception{
    if(head-tail==0&&full||(head==0&&(tail==0)&&full)){
      throw new Exception("full");
    }
    data[tail]=d;
    tail=tail+1;
    if(tail==data.length){
      tail=0;
    }
    if(head==tail){
      full=true;
    }
    
  }
  
  public int dequeue()throws Exception{
    if(head==tail&&!full||(head==data.length&&tail==0)){
      throw new Exception("empty");
    }
    full=false;
    head=head+1;
    if(head==data.length){
      head=0;
      return data[data.length-1];
    }else{
      return data[head-1];
    }
    
  }
  public static void main(String[] args)throws Exception {
    ArrayQueue queue=new ArrayQueue(10);
    for(int i=0;i<10;i++){
      queue.enqueue(i);
    }
    for(int i=0;i<10;i++){
      System.out.print(queue.dequeue()+" ");
    }
    System.out.println();
    for(int i=0;i<5;i++){
      queue.enqueue(i);
    }
    for(int i=0;i<3;i++){
      System.out.print(queue.dequeue()+" ");
    }
    System.out.println();
    for(int i=0;i<8;i++){
      queue.enqueue(i);
    }
    for(int i=0;i<10;i++){
      System.out.print(queue.dequeue()+" ");
    }
    System.out.println();

  }

}