Sha256: f3090ad26afa992031e7b362ba0fed099d3dd343a61846c773a5ccaddf0ce0a2
Contents?: true
Size: 1.24 KB
Versions: 94
Compression:
Stored size: 1.24 KB
Contents
public final class Deque<T> {
private Element<T> head;
public void push(T value) {
if (head == null) {
head = new Element<>(value, null, null);
head.next = head;
head.prev = head;
return;
}
Element<T> oldTail = head.prev;
Element<T> tail = new Element<>(value, oldTail, head);
oldTail.next = tail;
head.prev = tail;
}
public T pop() {
head = head.prev;
return shift();
}
public void unshift(T value) {
push(value);
head = head.prev;
}
public T shift() {
T value = head.value;
Element<T> newHead = head.next;
Element<T> newTail = head.prev;
if (newHead == head) {
head = null;
}
else {
newHead.prev = newTail;
newTail.next = newHead;
head = newHead;
}
return value;
}
private static final class Element<T> {
private final T value;
private Element<T> prev;
private Element<T> next;
public Element(T value, Element<T> prev, Element<T> next) {
this.value = value;
this.prev = prev;
this.next = next;
}
}
}
Version data entries
94 entries across 94 versions & 1 rubygems