원형 큐(Circular Queue)
- Linear Queue에 대한 개념만 읽고 코딩을 시작했는데 뭔가 비효율적이라는 생각이 들어서 효율적으로 구현하기 시작
- 그 결과 원형 큐(Circular Queue)가 되었다.
package dailyCoding; interface Queue{ boolean isEmpty(); void enQueue(char element); void deQueue(); void printQueue(); } class ArrayQueue implements Queue{ public int front; public int rear; public int size; public char arr[]; public int count; public ArrayQueue(int size){ this.size = size; this.front = -1; this.rear = -1; this.arr = new char[size]; this.count = -1; } @Override public boolean isEmpty() { if(rear < 0){ return true; } return false; } @Override public void enQueue(char element) { count++; System.out.print("enQueue ) " + (count+1) + " &&& ");
if(count > size-1){ count = size-1; System.out.println("It's full."); return; } rear++;
if(rear < size){ arr[rear] = element; }else{ rear = 0; if(rear < front){ arr[rear] = element; } } System.out.println("rear : " + rear + " front : " + front); } @Override public void deQueue() { if(count > -1){ count--; } System.out.print("deQueue ) " + (count+1) + " &&& "); if(!isEmpty()){ front++; if(front >= size){ front = 0; } if(front == rear){ System.out.println("It's empty!"); front = -1; rear = -1; }else if(front > size){ front = 0; } }else{ System.out.println("It's empty!"); } System.out.println("rear : " + rear + " front : " + front); } @Override public void printQueue(){ System.out.print("*** Print Queue :"); if(!isEmpty()){ if(front < rear && rear < size){ for(int i=front+1; i<=rear; i++){ System.out.print(" " + arr[i]); } }else{ if(rear < size ){ for(int i=0; i<=rear; i++){ System.out.print(arr[i] + " "); } for(int i=front+1; i<size; i++){ System.out.print(arr[i] + " "); } } } }else{ System.out.print("It's empty!"); } System.out.println(""); } } public class dailyCode{ public static void main(String []args){ ArrayQueue aq = new ArrayQueue(5); aq.enQueue('1'); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.enQueue('2'); aq.printQueue(); aq.enQueue('3'); aq.printQueue(); aq.enQueue('4'); aq.printQueue(); aq.enQueue('5'); aq.printQueue(); aq.enQueue('6'); aq.printQueue(); aq.enQueue('7'); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.enQueue('A'); aq.printQueue(); aq.enQueue('B'); aq.printQueue(); aq.enQueue('C'); aq.printQueue(); aq.enQueue('C'); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.deQueue(); aq.printQueue(); aq.enQueue('C'); aq.printQueue(); } } |