Mega Code Archive
Queue
<![CDATA[
class Queue {
private int maxSize;
private int[] queArray;
private int front;
private int rear;
private int nItems;
public Queue(int s) {
maxSize = s;
queArray = new int[maxSize];
front = 0;
rear = -1;
nItems = 0;
}
public void insert(int j) {
if (rear == maxSize - 1)
rear = -1;
queArray[++rear] = j;
nItems++;
}
public int remove() {
int temp = queArray[front++];
if (front == maxSize)
front = 0;
nItems--;
return temp;
}
public int peekFront() {
return queArray[front];
}
public boolean isEmpty() {
return (nItems == 0);
}
public boolean isFull() {
return (nItems == maxSize);
}
public int size() {
return nItems;
}
}
public class MainClass {
public static void main(String[] args) {
Queue theQueue = new Queue(5); // queue holds 5 items
theQueue.insert(10); // insert 4 items
theQueue.insert(20);
theQueue.insert(30);
theQueue.insert(40);
theQueue.remove(); // remove 3 items
theQueue.remove(); // (10, 20, 30)
theQueue.remove();
theQueue.insert(50); // insert 4 more items
theQueue.insert(60); // (wraps around)
theQueue.insert(70);
theQueue.insert(80);
while (!theQueue.isEmpty()) { // all items
int n = theQueue.remove(); // (40, 50, 60, 70, 80)
System.out.print(n);
System.out.print(" ");
}
System.out.println("");
}
}
40 50 60 70 80
]]>