展开的链表是由小数组组成的链表，它们的大小都相同，但每个数组的大小都很小，以至于插入或删除都很快，但又足够大以填充高速缓存行。指向列表的迭代器既包含指向节点的指针，又包含指向包含数组的节点的索引。它也是一种数据结构，是链表的另一种形式。它与B树有关。它可以在节点上存储元素数组，而不像普通的链表在节点上存储单个元素。它是数组和链表融合为一个的组合。它提高了缓存性能，并减少了与存储元数据引用相关的内存开销。在上一篇文章中已经提到了其他主要的优点和缺点。
先决条件：展开的链表简介
以下是展开的链表的插入和显示操作。
Input : 72 76 80 94 90 70
capacity = 3
Output : Unrolled Linked List :
72 76
80 94
90 70
Explanation : The working is well shown in the
algorithm below. The nodes get broken at the
mentioned capacity i.e., 3 here, when 3rd element
is entered, the flow moves to another newly created
node. Every node contains an array of size
(int)[(capacity / 2) + 1]. Here it is 2.
Input : 49 47 62 51 77 17 71 71 35 76 36 54
capacity = 5
Output :
Unrolled Linked List :
49 47 62
51 77 17
71 71 35
76 36 54
Explanation : The working is well shown in the
algorithm below. The nodes get broken at the
mentioned capacity i.e., 5 here, when 5th element
is entered, the flow moves to another newly
created node. Every node contains an array of
size (int)[(capacity / 2) + 1]. Here it is 3.
算法 ：
Insert (ElementToBeInserted)
if start_pos == NULL
Insert the first element into the first node
start_pos.numElement ++
end_pos = start_pos
If end_pos.numElements + 1 < node_size
end_pos.numElements.push(newElement)
end_pos.numElements ++
else
create a new Node new_node
move final half of end_pos.data into new_node.data
new_node.data.push(newElement)
end_pos.numElements = end_pos.data.size / 2 + 1
end_pos.next = new_node
end_pos = new_node
以下是插入和显示操作的Java实现。在下面的代码中，容量为5，并输入随机数。
Java
/* Java program to show the insertion operation
* of Unrolled Linked List */
import java.util.Scanner;
import java.util.Random;
// class for each node
class UnrollNode {
UnrollNode next;
int num_elements;
int array[];
// Constructor
public UnrollNode(int n)
{
next = null;
num_elements = 0;
array = new int[n];
}
}
// Operation of Unrolled Function
class UnrollLinkList {
private UnrollNode start_pos;
private UnrollNode end_pos;
int size_node;
int nNode;
// Parameterized Constructor
UnrollLinkList(int capacity)
{
start_pos = null;
end_pos = null;
nNode = 0;
size_node = capacity + 1;
}
// Insertion operation
void Insert(int num)
{
nNode++;
// Check if the list starts from NULL
if (start_pos == null) {
start_pos = new UnrollNode(size_node);
start_pos.array[0] = num;
start_pos.num_elements++;
end_pos = start_pos;
return;
}
// Attaching the elements into nodes
if (end_pos.num_elements + 1 < size_node) {
end_pos.array[end_pos.num_elements] = num;
end_pos.num_elements++;
}
// Creation of new Node
else {
UnrollNode node_pointer = new UnrollNode(size_node);
int j = 0;
for (int i = end_pos.num_elements / 2 + 1;
i < end_pos.num_elements; i++)
node_pointer.array[j++] = end_pos.array[i];
node_pointer.array[j++] = num;
node_pointer.num_elements = j;
end_pos.num_elements = end_pos.num_elements / 2 + 1;
end_pos.next = node_pointer;
end_pos = node_pointer;
}
}
// Display the Linked List
void display()
{
System.out.print("\nUnrolled Linked List = ");
System.out.println();
UnrollNode pointer = start_pos;
while (pointer != null) {
for (int i = 0; i < pointer.num_elements; i++)
System.out.print(pointer.array[i] + " ");
System.out.println();
pointer = pointer.next;
}
System.out.println();
}
}
/* Main Class */
class UnrolledLinkedList_Check {
// Driver code
public static void main(String args[])
{
Scanner sc = new Scanner(System.in);
// create instance of Random class
Random rand = new Random();
UnrollLinkList ull = new UnrollLinkList(5);
// Perform Insertion Operation
for (int i = 0; i < 12; i++) {
// Generate random integers in range 0 to 99
int rand_int1 = rand.nextInt(100);
System.out.println("Entered Element is " + rand_int1);
ull.Insert(rand_int1);
ull.display();
}
}
}C#
/* C# program to show the insertion operation
* of Unrolled Linked List */
using System;
// class for each node
public class UnrollNode {
public UnrollNode next;
public int num_elements;
public int[] array;
// Constructor
public UnrollNode(int n)
{
next = null;
num_elements = 0;
array = new int[n];
}
}
// Operation of Unrolled Function
public class UnrollLinkList {
private UnrollNode start_pos;
private UnrollNode end_pos;
int size_node;
int nNode;
// Parameterized Constructor
public UnrollLinkList(int capacity)
{
start_pos = null;
end_pos = null;
nNode = 0;
size_node = capacity + 1;
}
// Insertion operation
public void Insert(int num)
{
nNode++;
// Check if the list starts from NULL
if (start_pos == null) {
start_pos = new UnrollNode(size_node);
start_pos.array[0] = num;
start_pos.num_elements++;
end_pos = start_pos;
return;
}
// Attaching the elements into nodes
if (end_pos.num_elements + 1 < size_node) {
end_pos.array[end_pos.num_elements] = num;
end_pos.num_elements++;
}
// Creation of new Node
else {
UnrollNode node_pointer = new UnrollNode(size_node);
int j = 0;
for (int i = end_pos.num_elements / 2 + 1;
i < end_pos.num_elements; i++)
node_pointer.array[j++] = end_pos.array[i];
node_pointer.array[j++] = num;
node_pointer.num_elements = j;
end_pos.num_elements = end_pos.num_elements / 2 + 1;
end_pos.next = node_pointer;
end_pos = node_pointer;
}
}
// Display the Linked List
public void display()
{
Console.Write("\nUnrolled Linked List = ");
Console.WriteLine();
UnrollNode pointer = start_pos;
while (pointer != null) {
for (int i = 0; i < pointer.num_elements; i++)
Console.Write(pointer.array[i] + " ");
Console.WriteLine();
pointer = pointer.next;
}
Console.WriteLine();
}
}
/* Main Class */
public class UnrolledLinkedList_Check {
// Driver code
public static void Main(String[] args)
{
// create instance of Random class
Random rand = new Random();
UnrollLinkList ull = new UnrollLinkList(5);
// Perform Insertion Operation
for (int i = 0; i < 12; i++) {
// Generate random integers in range 0 to 99
int rand_int1 = rand.Next(100);
Console.WriteLine("Entered Element is " + rand_int1);
ull.Insert(rand_int1);
ull.display();
}
}
}
// This code has been contributed by 29AjayKumar输出：
Entered Element is 90
Unrolled Linked List =
90
Entered Element is 3
Unrolled Linked List =
90 3
Entered Element is 12
Unrolled Linked List =
90 3 12
Entered Element is 43
Unrolled Linked List =
90 3 12 43
Entered Element is 88
Unrolled Linked List =
90 3 12 43 88
Entered Element is 94
Unrolled Linked List =
90 3 12
43 88 94
Entered Element is 15
Unrolled Linked List =
90 3 12
43 88 94 15
Entered Element is 7
Unrolled Linked List =
90 3 12
43 88 94 15 7
Entered Element is 67
Unrolled Linked List =
90 3 12
43 88 94
15 7 67
Entered Element is 74
Unrolled Linked List =
90 3 12
43 88 94
15 7 67 74
Entered Element is 85
Unrolled Linked List =
90 3 12
43 88 94
15 7 67 74 85
Entered Element is 48
Unrolled Linked List =
90 3 12
43 88 94
15 7 67
74 85 48
时间复杂度： O(n)
另外，实际应用很少：
- 它用于B树和T树
- 用于哈希阵列树
- 在跳过列表中使用
- 用于CDR编码