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Data Structure (Part 2) - Linear List

2024-07-12

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Table of contents

1. Basic Concepts

2. Basic operations of linear tables

3. Sequence table

(1) Static allocation

(2) Dynamic allocation

(3). Insertion and deletion of sequence lists (taking static allocation as an example) (the sample code contains the following necessary basic functions)

(4) Search by position or by value

4. Linked List

(1) Singly linked list

i. Definition of a singly linked list (with a head node)

1. Basic Concepts

Linear table:

(1). Each element,Same data type。

(2) Between elements,Orderly。

(3) BothHeader ElementsandFooter element。

(4) Except for the header and footer, each element can be foundDirect front driveandDirect successor。

2. Basic operations of linear tables

TableFrom Nothing to Something

InitList(&L)：initializationA linear table

DestroyList(&L)：destroy

。

ListInsert(&L, i, e)：insert, insert element e at the i-th position in table L

ListDelete(&L, i, &e)：delete, delete the element at position i in table L, and return the deleted element using e

。

LocateElem(L, e): PressvalueSearch, search for the element with a specific keyword e in the table, and return the position of e, not the subscript

GetElem(L, i): PressBitFind and get the value of the i-th element in the table

。

Other general operations:

Length(L): FindTable lengthSpend

PrintList(L)：OutputTableallelement

Empty(L): Judgment tableIs it empty?, returns true or false

Highly summarized, that is, creation and sales and addition, deletion, modification and query

3. Sequence table

bySequential storageLinear table to store data

(1) Static allocation

  1. #define MAX 10
  2. //顺序表（静态分配）
  3. class SqList
  4. {
  5. public:
  6.     int data[MAX];
  7.     int length;
  8. };
  9. //初始化
  10. void InitList(SqList &l)
  11. {
  12.     for(int i = 0 ;i < 10 ;i++)
  13.     {
  14.         l.data[i] = 0;
  15.     }
  16.     l.length = 0;
  17. }
  18. //打印所有元素
  19. void PrintList(SqList &l)
  20. {
  21.     for (int i = 0; i < 10; i++)
  22.         cout << "第" << i << "个数：" << l.data[i] << endl;
  23. }
  24.  
  25. //测验
  26. void test01()
  27. {
  28.     SqList l;
  29.     InitList(l);
  30.     PrintList(l);
  31. }

(2) Dynamic allocation

  1. #define InitSize 10
  2. //顺序表（动态分配）
  3. class SqList
  4. {
  5. public:
  6. 	int* data;		//指示动态分配数组的指针
  7. 	int MaxSize;	//指示最大容量
  8. 	int length;		//指示当前长度
  9. };
  10. //初始化顺序表
  11. void InitList(SqList& l)
  12. {
  13. 	l.data = new int[InitSize];
  14. 	l.MaxSize = InitSize;
  15. 	l.length = 0;
  16. 	for (int i = 0; i < l.MaxSize; i++)
  17. 	{
  18. 		l.data[i] = 0;
  19. 	}
  20. }
  21. //增长数组空间
  22. void IncreaseSize(SqList& l, int len)
  23. {
  24. 	int* p = l.data;					//暂存原数组中的数据
  25. 	l.data = new int[10 + len];			//扩展新的数组
  26. 	for (int i = 0; i < l.length; i++)	//将原数据拷贝进新数组中
  27. 	{
  28. 		l.data[i] = p[i];
  29. 	}
  30. 	l.MaxSize = InitSize + len;			//修改数组的状态数据
  31. 	delete p;							//将p释放
  32. }
  33. //打印所有元素
  34. void PrintList(SqList& l)
  35. {
  36. 	for (int i = 0; i < 10; i++)
  37. 		cout << "第" << i << "个数：" << l.data[i] << endl;
  38. }
  39.  
  40. void test01()
  41. {
  42. 	SqList l;
  43. 	InitList(l);
  44. 	PrintList(l);
  45. }

(3). Insertion and deletion of sequence lists (taking static allocation as an example) (the sample code contains the following necessary basic functions)

//insert

bool ListInsert(SqList& l, int d, int e)
{
if (l.length &gt;= MAX) //First, determine whether the table is full and whether the insertion is legal
    {
cout &lt;&lt; "Insert failed, upper limit reached" &lt;&lt; endl;
        return false;
    }
        
    if (d < 1 || d > l.length + 1)
    {
cout &lt;&lt; "Insert failed, no direct predecessor" &lt;&lt; endl;
        return false;
    }
for (int j = l.length; j &gt;= d; j--) //Move the element after the insertion point backward
        l.data[j] = l.data[j - 1];
l.data[d - 1] = e; //Insert, because d refers to the number, it should be subtracted in the array conversion
    l.length++;
    return true;
}

//delete
bool ListDelete(SqList& l, int d, int &e)
{
if (d &lt; 1 || d &gt;l.length) //Judge whether the deleted position is legal
        return false;
e = l.data[d - 1]; //temporarily store the deleted elements
for (int j = d; j &lt; l.length; j++) //Move the elements after the deleted element forward
l.data[j - 1] = l.data[j]; //Here, j = d, j-1 is overwritten by j. If j = d-1, the following overwriting will become j is overwritten by j+1, and j+1 may exceed the maximum capacity of the array in the end.
    l.length--;
    return true;
}

Sample Code

  1. #define MAX 10
  2. //顺序表（静态分配）
  3. class SqList
  4. {
  5. public:
  6.     int data[MAX];
  7.     int length;
  8. };
  9. //初始化
  10. void InitList(SqList& l)
  11. {
  12.     for (int i = 0; i < 10; i++)
  13.     {
  14.         l.data[i] = 0;
  15.     }
  16.     l.length = 0;
  17. }
  18. //打印所有元素
  19. void PrintList(SqList& l)
  20. {
  21.     for (int i = 0; i < 10; i++)
  22.         cout << "第" << i << "个数：" << l.data[i] << endl;
  23. }
  24. //存入数据
  25. void InputElem(SqList& l, int e)
  26. {
  27.     int i = 0;
  28.     while (i < MAX)
  29.     {
  30.         if (l.data[i] == 0)
  31.         {
  32.             l.data[i] = e;
  33.             l.length++;
  34.             break;
  35.         }
  36.         i++;
  37.     }
  38. }
  39. //获取顺序表长度
  40. int GetLength(SqList l)
  41. {
  42.     //cout << l.length << endl;
  43.     return l.length;
  44. }
  45. //插入
  46. bool ListInsert(SqList& l, int d, int e)
  47. {
  48.     if (l.length >= MAX)                        //首先要判断表是否已满、插入是否合法
  49.     {
  50.         cout << "插入失败，已达上限" << endl;
  51.         return false;
  52.     }
  53.         
  54.     if (d < 1 || d > l.length + 1)
  55.     {
  56.         cout << "插入失败,无直接前驱" << endl;
  57.         return false;
  58.     }
  59.     for (int j = l.length; j >= d; j--)         //将插入点之后的元素后移
  60.         l.data[j] = l.data[j - 1];
  61.     l.data[d - 1] = e;                          //插入，因为d指的是第几个数，在数组的换算中要减一
  62.     l.length++;
  63.     return true;
  64. }
  65. //删除
  66. bool ListDelete(SqList& l, int d, int &e)
  67. {
  68.     if (d < 1 || d >l.length)                   //判断删除的位置是否合法
  69.         return false;
  70.     e = l.data[d - 1];                          //暂存删除掉的元素
  71.     for (int j = d; j < l.length; j++)          //将被删除元素之后的元素前移
  72.         l.data[j - 1] = l.data[j];              //此处，必须是j = d，j-1被j覆盖，若j = d-1，则下文的覆盖会变为j 被j+1 覆盖，而j+1在最后有可能会超过数组的最大容量
  73.     l.length--;
  74.     return true;
  75. }
  76.  
  77. //查看情况
  78. void CheckList(SqList& l)
  79. {
  80.     PrintList(l);
  81.     cout << "当前长度为" << GetLength(l) << endl;
  82. }
  83.  
  84. //测验
  85. void test01()
  86. {
  87. 	SqList l;
  88. 	InitList(l);
  89.     
  90.     //输入部分数据
  91.     InputElem(l, 1);
  92.     InputElem(l, 2);
  93.     InputElem(l, 3);
  94.     InputElem(l, 4);
  95.     CheckList(l);
  96.  
  97.     //开始插入
  98.     if(ListInsert(l, 3, 6))
  99.         CheckList(l);
  100.  
  101.     //开始删除
  102.     int a = -1;
  103.     if (ListDelete(l, 2, a))
  104.         CheckList(l);
  105. }

(4) Search by position or by value

Very simple, no more details

  1. //判断d的合法性
  2. bool JugdeD(SqList l, int d)
  3. {
  4.     if (d < 1 || d > l.length)
  5.         return false;
  6.     return true;
  7. }
  8.  
  9. //按位序查找
  10. int GetElem(SqList l, int d)
  11. {
  12.     if (JugdeD(l, d))
  13.         return l.data[d - 1];
  14.     return 0;
  15. }
  16.  
  17. //按值查找
  18. int LocateElem(SqList l, int e)
  19. {
  20.     for (int i = 0; i < l.length; i++)
  21.     {
  22.         if (l.data[i] == e)       //数组储存的数据，若是类等复杂的数据类型，则需要对等号进行重载
  23.             return i + 1;
  24.     }
  25.     return 0;
  26. }
  27. //其余代码与上文相同
  28. //其中，JugdeD函数可以替换上文插入与删除中对位序合法性的判别————封装

4. Linked List

byChain storageLinear table to store data

(1) Singly linked list

i. Definition of a singly linked list (with a head node)

  1. //单链表
  2. class LNode
  3. {
  4. public:
  5.     int data;           //数据域，存放数据
  6.     LNode* next;        //指针域，指向下一个节点
  7. };
  8. //用using关键字给类起别名，用LinkList指代的是头结点，代表的是整个链表
  9. using LinkList = LNode*;
  10.  
  11. //初始化
  12. bool InitList(LinkList& L)
  13. {
  14.     L = new LNode();
  15.     if (L == nullptr)   //如果成立，则说明内存不足，分配失败
  16.         return false;
  17.     L->next = nullptr;
  18.     return true;
  19. }

ii. Insertion and deletion (header node)

For nodes without a head node, pay attention to the changes in the head pointer, and the rest are similar.

Insert (Normal Edition)

  1. //插入
  2. bool ListInsert(LinkList& L, int i, int e)
  3. {
  4.     if (i < 1)                          //判断插入位点是否合法[1]——i值的合法性
  5.     {
  6.         cout << "i为负数" << endl;
  7.         return false;
  8.     }    
  9.     LNode* p = L;                       //让p与L指向相同的位点，L是指示头指针的，所以L是不能改变的
  10.     LNode* s = new LNode();             //新的数据储存
  11.     s->data = e;
  12.     while (p != nullptr && i != 1)      //由头结点起始，开始遍历寻找对应位点
  13.     {
  14.         p = p->next;
  15.         i--;
  16.     }
  17.     if (p == nullptr)                   //判断插入的位点是否合法[2]——i值对应的节点的合法性
  18.     {
  19.         cout << "插入位点超出实际长度" << endl;
  20.         return false;
  21.     }                     
  22.     s->next = p->next;                  //开始接轨，顺序不能乱
  23.     p->next = s;
  24.     return true;
  25. }

Insert (package version)

  1. //特定节点的后插操作
  2. bool InsertNextNode(LNode* p, int e)
  3. {
  4.     if (p == nullptr)                   
  5.     {
  6.         cout << "插入位点超出实际长度" << endl;
  7.         return false;
  8.     }
  9.     LNode* s = new LNode();
  10.     s->data = e;
  11.     s->next = p->next;
  12.     p->next = s;
  13.     return true;
  14. }
  15. //插入
  16. bool ListInsert(LinkList& L, int i, int e)
  17. {
  18.     if (i < 1)                          //判断插入位点是否合法[1]——i值的合法性
  19.     {
  20.         cout << "i为负数" << endl;
  21.         return false;
  22.     }    
  23.     LNode* p = L;                       //让p与L指向相同的位点，L是指示头指针的，所以L是不能改变的
  24.     while (p != nullptr && i != 1)      //由头结点起始，开始遍历寻找对应位点
  25.     {
  26.         p = p->next;
  27.         i--;
  28.     }
  29.     return InsertNextNode(p, e);        //被封装了的部分
  30. }

 

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