Flatten a Multilevel Doubly Linked List 2020-09-21 23:39
public Node flatten(Node head) {
if (head == null) {
return null;
}
Node cur = head;
while (cur != null) {
if (cur.child != null) {
Node next = cur.next;
cur.next = flatten(cur.child);
cur.child = null;
cur.next.prev = cur;
if (next != null) {
while (cur.next != null) {
cur = cur.next;
}
cur.next = next;
next.prev = cur;
}
}
cur = cur.next;
}
return head;
}
| Runtime | Memory |
|---|---|
| 1 ms | 37.7 MB |
EOF