24王道数据结构课后综合应用题

菜菜大学生自学数据结构，以下为24王道数据结构课后习题自己作答的集合，欢迎各路大佬指认错误 ~

持续学习，持续更新~

一. 顺序表

01.删除顺序表中最小的元素并返回值，空出的位置用最后一个元素来填补，若表为空，则显示错误信息并退出运行。

#include
using namespace std;
typedef struct{
	int data[10] = {15, 16, 18, 10, 100, 15, 19, 14, 8};
	int length = 9;
}sqlist;
int findmin(sqlist L)
{
	int min = L.data[0], I = 0;
	for(int i = 1; i < L.length; i++)
		if(L.data[i] < min)
		{
			min = L.data[i];
			I = i;
		}
	return I;
}
bool deletelist(sqlist &L, int &key)
{
	if(L.length == 0 )
	{
		cout << "这是一个空列表" << endl;
		return false;
	}
	key = L.data[findmin(L)];
	L.data[findmin(L)] = L.data[L.length-1];
	L.length--;
	return true;
}
int main()
{
	sqlist L;
	int key = -1;
	deletelist(L, key);
	cout << key << endl;
	for (int i = 0; i < L.length; i++)
		cout << L.data[i] << " " << endl; 
	cout << L.length << endl;
	
	system("pause");
	return 0;
}

 02.设置高效算法，将顺序表中的元素逆置

#include
using namespace std;
#define maxsize 10
typedef struct{
	int data[maxsize] = {1, 2, 3, 4, 5, 6, 7, 8, 9};
	int length = 9;
}sqlist;
void reverse(sqlist &L)
{
	for(int i = 0;i < L.length/2; i++)
		swap(L.data[i], L.data[L.length - i - 1]);
}
void swap(int &a, int &b)
{
	a = a + b;
	b = a - b;
	a = a - b;
}
int main()
{
	sqlist L;
	reverse(L);
	for (int i = 0; i < L.length; i++)
		cout << L.data[i] << "\t";
	system("pause");
	return 0;
 } 

03.删除长度为n的顺序表中所有值为x的数据元素

#include
using namespace std;
#define maxsize 10
typedef struct{
	int data[maxsize];
	int length;
}sqlist;
void DeleteElem(sqlist &L, int key)
{
	for (int i = 0; i < L.length; i++)
		cout << L.data[i] << " ";
	cout << endl;
	int k = 0;
	for (int i = 0; i < L.length; i++)
		if (L.data[i] != key)
		{
			L.data[k] = L.data[i];
			k++;
		}
		else
			cout << "等于key的元素值所在位置:" << i+1 << endl;
	L.length = k;
}
void Initlist(sqlist &L, int length)
{
	L.length = 0;
	for(int i = 0; i < length; i++)
	{
		cout << "输入第" << i+1 << "个数据："; 
		cin >> L.data[i];
		L.length++;
	}
}
int main()
{
	sqlist L;
	int size;
	cout << "数组长度: " ;
	cin >> size;
	Initlist(L, size);
	cout << "长度：" << L.length << endl;
	int key;
	cout << "目的数据：";
	cin  >> key;
	DeleteElem(L, key);
	cout << L.length << endl;
	for (int i = 0; i < L.length; i++)
		cout << L.data[i] << " ";
	system("pause");
	return 0;
}

 04.删除有序顺序表中值位于s~t的所有元素，若s，t不合理或顺序表为空，返回错误信息 && 05.删除顺序表中值位于s~t的所有元素

#include
using namespace std;
#define maxsize 20
typedef struct{
	int data[maxsize];
	int length;
}sqlist;
bool DeleteElem(sqlist &L, int s, int t)
{
	if(s >= t || L.length == 0)
	{
		cout << "warning!" << endl;
		return false;
	}
	int k = 0;
	for(int i = 0; i < L.length; i++)
		if(L.data[i] < s || L.data[i] > t)
			L.data[k++] = L.data[i];
	L.length = k; 
}
void AddElem(sqlist &L, int length)
{
	L.length = length;
	for(int i = 0; i < length; i++)
		cin >> L.data[i];
}
int main()
{
	sqlist L;
	int length;
	cin >> length; 
	AddElem(L,length);
	int s, t;
	cin >> s >> t;
	DeleteElem(L, s, t);
	cout << L.length << endl;
	for(int i = 0;i < L.length; i++)
		cout << L.data[i] << " ";
	system("pause");
	return 0;
 } 

06.从有序顺序表中删除所有其值重复的元素，使表中元素值各不相同

#include
using namespace std;
#define maxsize 20
typedef struct{
	int data[maxsize];
	int length;
}sqlist;
void InitElem(sqlist &L, int length)
{
	L.length = length;
	for(int i = 0; i < length; i++)
		cin >> L.data[i];
}
bool DeleteElem(sqlist &L)
{
	int count = 0;
	for(int i = 1; i < L.length; i++)
		if(L.data[count] != L.data[i])
			L.data[++count] = L.data[i];
	L.length = count+1;
}
int main()
{
	sqlist L;
	int length;
	cin >> length; 
	InitElem(L,length);
	DeleteElem(L);
	cout << L.length << endl;
	for(int i = 0;i < L.length; i++)
		cout << L.data[i] << " ";
	system("pause");
	return 0;
}

07.将两个有序顺序表合并为一个顺序表

#include
using namespace std;
#define maxsize 20
typedef struct{
	int data[maxsize];
	int length;
}sqlist;
void InitElem(sqlist &L, int length)
{
	L.length = length;
	for(int i = 0; i < length; i++)
		cin >> L.data[i];
}
bool Add(sqlist &L, sqlist &I, sqlist &S)
{
	if(L.length + I.length > maxsize)
		return false;
	int i = 0, j = 0, k = 0;
	while(i < L.length && j < I.length)
		if(L.data[i] >= I.data[j])
			S.data[k++] = I.data[j++];
		else
			S.data[k++] = L.data[i++];
	while(i < L.length)
		S.data[k++] = L.data[i++];
	while(j < I.length)
		S.data[k++] = I.data[j++];
	S.length = k;
	return true; 
}
int main()
{
	sqlist A, B, C;
	int a, b;
	cin >> a;
	InitElem(A, a);
	cin >> b;
	InitElem(B, b);
	Add(A, B, C);
	for(int i = 0; i < C.length; i++)
		cout << C.data[i] << " ";
	system("pause");
	return 0;
}

08.将数组中两个顺序表的位置互换

#include
using namespace std;
#define maxsize 10
typedef struct{
	int length;
	int data[maxsize];
}sqlist;
void add(sqlist &A, sqlist &B, int * p, int a)
{
	for(int i = 0; i < maxsize - a; i++)
		p[i] = B.data[i];
	for(int i = maxsize - a; i < maxsize; i++)
		p[i] = A.data[i - maxsize + a];
}
void part(sqlist &B, sqlist &C, int * p, int a)
{
	for (int i = 0; i < a; i++)
		B.data[i] = p[i];
	for(int i = a; i < maxsize; i++)
		C.data[i-a] = p[i];
	add(B, C, p, a);
}

int main()
{
	sqlist B, C;
	int num[maxsize] = {1, 5, 6, 9, 10, 15, 16, 19, 20, 25};
	int a;
	cin >> a;
	B.length = a;
	C.length = maxsize - a;
	part(B, C, num, a);
	for(int i = 0; i < maxsize; i++)
		cout << num[i] << " ";
	system("pause");
	return 0;
}

09.在递增的顺序表中最快的查找其值为x的元素，若找到，则将其与后继元素交换位置，若找不到，则将其插入进表中并保证顺序表仍递增

#include
using namespace std;
#define maxsize 20
typedef struct{
	int data[maxsize];
	int length;
}sqlist; 
int LocateElem(sqlist L, int key) // 折半查找法 
{
	int left = 0, right = L.length - 1;
	while(left <= right)
	{
		int mid = (left + right)/2;
		if(L.data[mid] > key)
			right = mid - 1;
		else if (L.data[mid] < key)
			left = mid + 1;
		else
			return mid;
	}
	return -1;
}
void swap(int &a, int &b) // 交换函数 
{
	a = a + b;
	b = a - b;
	a = a - b;
}
bool ListInsert(sqlist &L, int i, int key) // 指定位置插入元素 
{
	if(i > L.length+1 || i < 1)
		return false;
	if(L.length >= maxsize)
		return false;
	for(int j=L.length; j>=i; j--)
		L.data[j] = L.data[j-1];
	L.data[i-1] = key;
	L.length++;
	return true;
}
bool find(sqlist &L, int key)
{
	int i = LocateElem(L, key);
	if(i != -1)// 如果可以找到 
		if(i != L.length-1) // 不是最后一个元素 
		{
			swap(L.data[i], L.data[i+1]);
			return true;
		}
		else // 是最后一个元素 
			return true;
	for(int i = 0; i < L.length-1; i++) // 找到合适的插入位置 
		if(key >= L.data[i] && key < L.data[i+1])
		{
			ListInsert(L, i+2, key);
			return true;
		}
	ListInsert(L, L.length+1, key); // 没有合适的插入位置 
	return true;
			
}
void InitElem(sqlist &L, int length)
{
	L.length = length;
	for(int i = 0; i < length; i++)
		cin >> L.data[i];
}
int main()
{
	sqlist L;
	int length;
	cin >> length;
	InitElem(L, length); 
	int key;
	cin >> key;
	find(L, key);
	for(int i = 0; i < L.length; i++)
		cout << L.data[i] << " ";
	system("pause");
	return 0;
}

10.将数组中的元素循环左移p个单位

/*
设计思路：
将数组分为[0, step - 1]与[step, n-1]两段
交换两段位置 
*/

#include
using namespace std;
#define maxsize 20
void addElem(int * p, int size)
{
	for(int i = 0; i < size; i++)
		cin >> p[i];
}
void reverse(int * p, int left, int right) // 倒置指定段元素 
{
	int mid = (right - left + 1) / 2;
	for(int i = 0; i < mid; i++)
	{
		p[left + i] = p[left + i] + p[right - i]; 
		p[right - i] = p[left + i] - p[right - i]; 
		p[left + i] = p[left + i] - p[right - i]; 
	}
}
int main()
{
	int R[maxsize];
	int size;
	cin >> size;
	addElem(R, size);
	int step;
	cin >> step;
	reverse(R, 0, step - 1);
	reverse(R, step, size - 1);
	reverse(R, 0, size - 1);
	for(int i = 0; i < size; i++)
		cout << R[i] << " ";
	system("pause");
	return 0;
}

/*
空间复杂度：O(1) 
时间复杂度：O(n) 
*/

11.找到两个等长递增序列A与B的中位数

/*
先按递增顺序合并两个序列 
再判断合序列的长度是偶数还是奇数
最后找中位数 
*/
#include
using namespace std;
#define maxsize 10
void add(float * p, int size)
{
	for(int i = 0; i < size; i++)
		cin >> p[i];
}
float find(float * p, int size)
{
	if(size % 2 != 0)
		return p[size/2];
	else 
		return (p[size/2] + p[(size/2)-1])/2;
}
void andand(float * p, float * q, float * num, int size1, int size2)
{
	int i = 0, j = 0, k = 0;
	while(i <= size1 && j <= size2)
		if(p[i] < q[j])
			num[k++] = p[i++];
		else
			num[k++] = q[j++];
	while(i <= size1)
		num[k++] = p[i++];
	while(j <= size2)
		num[k++] = q[j++];
}
int main()
{
	float num1[maxsize], num2[maxsize];
	int size1, size2;
	cin >> size1 >> size2;
	add(num1, size1);
	add(num2, size2);
	float num[maxsize];
	if(size1 + size2 > maxsize)
	{
		cout << "数据错误" << endl;
		return 0;
	}
	andand(num1, num2, num, size1, size2);
	int size = size1 + size2;
	cout << find(num, size) << endl;
	system("pause");
	return 0;
}
/*
时间复杂度：O(n) 
空间复杂度：O(1) 
*/

12.找出顺序表A中的主元素，若找不到，则输出-1

/*
已知一个整数序列a长度为n，其中若存在a中的个数大于n/2则称为a的主元素 
*/
#include
using namespace std;
#define maxsize 20 
int FindMain(int * num, int size)
{
	int count[maxsize] = {0}, max = count[0], x;
	for(int i = 0; i < size; i++)
		if(++count[num[i]] > max)
		{
			x = num[i];
			max = count[x];
		}
	if(count[x] > size / 2)
		return x;
	else
		return -1;
}
int main()
{
	int num[maxsize];
	int size;
	cin >> size;
	for(int i = 0; i < size; i++)
		cin >> num[i];
	cout << FindMain(num, size) << endl;
	system("pause");
	return 0;
}
/*
时间复杂度 O(n)
空间复杂度 O(1) 
*/
// 更优算法：Boyer-Moore投票算法
/*
1. 初始化一个候选主元素candidate和计数器count为0。
2. 遍历数组，当count为0时，将当前元素设为候选主元素。
3. 如果当前元素与候选主元素相同，则增加计数器count；否则，减少计数器count。
4. 验证候选主元素：对候选主元素进行验证，确保它出现次数超过一半。
重新遍历数组，统计候选主元素出现的次数。
如果出现次数超过一半，返回候选主元素；否则，表示没有主元素，返回-1。 
*/

13.输出一个数组中未出现的最小整数

/*
先找到序列中的最大值，+1作为count数组的长度 
对序列中每个数字进行统计，非正整数不计，避免count数组出错
遍历count数组，输出第一个count为零的i值 
*/
#include
using namespace std;
#define maxsize 20

int find_min(int * num, int size, int max)
{
	int count[max + 1] = {0};
	for(int i = 0; i < size; i++)
		if(num[i] >= 1)
			count[num[i]]++;
	for(int i = 1; i <= max; i++)
		if(count[i] == 0)
			return i;	
	return max+1;
}
int size_max(int * num, int size)
{
	int max = num[0];
	for(int i = 1; i < size; i++)
		if(num[i] > max)
			max = num[i];
	return max;
}
int main()
{
	int num[maxsize];
	int size;
	cin >> size;
	for(int i = 0; i < size; i++)
		cin >> num[i];
	cout << find_min(num, size, size_max(num, size)) << endl;
	system("pause");
	return 0;
}
/*
时间复杂度 O(n)
空间复杂度 O(n)
*/

14.给定三个升序整数集合，计算并输出所有可能的三元组中的最小距离

/*
设a为最小值，c为最大值，则 D = 2 * abs(c-a), 与中值b无关 
固定三组中的c，寻找满足条件的a
不断更新Dmin 
*/
#include
#include
using namespace std;
#define max 0x7fffffff
#define maxsize 20
bool ifmin(int a, int b, int c)
{
	if(a <= b && a <= c)
		return true;
	return false;
}
int find(int * A, int * B, int * C, int sizea, int sizeb, int sizec)
{
	int D, Dmin = max, i = 0, j = 0, k = 0;
	int d, e, f; 
	while(i <= sizea && j <= sizeb && k <= sizec)
	{
		int a = A[i], b = B[j], c = C[k];
		D = abs(a - b) + abs(b - c) + abs(c - a);
		if(D <= Dmin)
		{
			d = a, e = b, f = c;
			Dmin = D;
		}
		if(ifmin(a, b, c))
			i++;
		else if(ifmin(b, c, a))
			j++;
		else
			k++;
	}
	return Dmin;
} 
int main()
{
	int A[3] = {-1, 0, 9}, B[4] = {-25, -10, 10, 11}, C[5] = {2, 9, 17, 30, 41};
	cout << find(A, B, C, 3, 4, 5) << endl;
	system("pause");
	return 0;
}
/*
时间复杂度 O(n)
空间复杂度 O(1)
*/

二. 链表

01.设计一个递归算法，删除不带头结点的单链表L中所有值为x的结点

#include
using namespace std;
typedef struct LNode{ // 定义单链表 
	int data;
	LNode *next;
}LNode, *LinkList;
void TailForm(LinkList &L, int length) // 尾插法建立链表 
{
	L = new LNode;
	L = NULL; // 初始化一个不带头结点的单链表 
	int i = 1, x;
	LNode * p = L;
	cout << "删除前：" << endl; 
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		if(p == NULL)
		{
			L = s;
			p = s;
		}
		else
		{
			p -> next = s;
			p = s;
		}
		i++; 
	}
	p -> next = NULL;
}
void Output(LinkList L) // 输出一个不带头结点的单链表中所有的值 
{
	LNode * p = L;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void DeleteP(LNode * &p) // 删除p结点 
{
	if(p == NULL)
		return; 
	if(p -> next == NULL)
	{
		p = NULL;
		return;
	}
	LNode * q = p -> next;
	p -> data = q -> data;
	p -> next = q -> next;
	delete(q);  
}
bool Delx(LinkList &L, int x)
{
	if(L == NULL)
		return false;
	LNode * p = L;	 
	LNode * prev = NULL; // 用于记录上一个节点
    while (p != NULL)
        if (p ->data == x)
            if (prev != NULL)
            {
            	// 删除p节点
                DeleteP(p);
                prev->next = p;
            }
            else
            {
                // 删除头节点
                L = L->next;
                delete p;
                p = L;
            }
        else
        {
            prev = p;
            p = p->next;
        }
	return true;
}
int main()
{
	LinkList L;
	int length;
	cout << "请输入单链表的长度:" << endl;
	cin >> length;
	TailForm(L, length);
	int x;
	cout << "请输入要删除的结点的值:" << endl;
	cin >> x;
	Delx(L, x);
	cout << "删除后：" << endl;
	Output(L);
	system("pause");
	return 0;
} 

02.删除带头结点的单链表L中所有值为x的结点

// 貌似与上一题类似，几乎照抄上一题，偷个懒

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
void TailForm(LinkList &L, int length) // 尾插法建立链表 
{
	L = new LNode;
	L -> next = NULL; // 初始化一个带头结点的单链表 
	int i = 1, x;
	LNode * p = L; 
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void DeleteP(LNode * &p) // 删除p结点 
{
	if(p == NULL)
		return; 
	if(p -> next == NULL)
	{
		p = NULL;
		return;
	}
	LNode * q = p -> next;
	p -> data = q -> data;
	p -> next = q -> next;
	delete(q);  
}
bool Delx(LinkList &L, int x)
{
	if(L -> next == NULL)
		return false;
	LNode * p = L -> next;	 
	LNode * prev = NULL; // 用于记录上一个节点
    while (p != NULL)
        if (p ->data == x)
            if (prev != NULL)
            {
            	// 删除p节点
                DeleteP(p);
                prev->next = p;
            }
            else
            {
                // 删除头节点
                L = L->next;
                delete p;
                p = L;
            }
        else
        {
            prev = p;
            p = p->next;
        }
	return true;
}
int main()
{
	LinkList L;
	int length;
	cin >> length;
	TailForm(L, length);
	int x;
	cin >> x;
	Delx(L, x);
	Output(L);
	system("pause");
	return 0;
}

03.从尾到头反向输出单链表的值

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList; 
bool InitLinkList(LinkList &L)
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void TailForm(LinkList &L, int length) // 尾插法建立链表 
{
	InitLinkList(L);
	int i = 1, x;
	LNode * p = L; 
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void HeadForm(LinkList L, LinkList &T, int length) // 利用头插法对单链表实现逆置 
{
	if(L -> next == NULL)
		return;
	InitLinkList(T);
	LNode * p = L -> next;
	while(p != NULL)
	{
		LNode * s = new LNode;
		s -> data = p -> data;
		s -> next = T -> next;
		T -> next = s;
		p = p -> next;
	}
}
void reverse(LinkList L, int length)
{
	LinkList T;
	TailForm(L, length);
	HeadForm(L, T, length);
	Output(T);
} 

int main()
{
	LinkList L;
	int length;
	cin >> length;
	reverse(L, length);
	system("pause");
	return 0;
}

04.在带头结点的单链表中删除一个最小值的结点

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L)
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void TailForm(LinkList &L, int length) // 尾插法建立链表 
{
	L = new LNode;
	L -> next = NULL; // 初始化一个带头结点的单链表 
	int i = 1, x;
	LNode * p = L; 
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void DeleteP(LNode * &p) // 删除p结点 
{
	if(p == NULL)
		return; 
	if(p -> next == NULL)
	{
		p = NULL;
		return;
	}
	LNode * q = p -> next;
	p -> data = q -> data;
	p -> next = q -> next;
	delete(q);  
}
void findmin(LinkList &L, int length)
{
	TailForm(L, length);
	LNode * p = L -> next;
	LNode * minp = p;
	int min = p -> data;
	while(p != NULL)
	{
		if(p -> data < min)
		{
			min = p -> data;
			minp = p;
		}
		p = p -> next; 
	}
	DeleteP(minp);
	Output(L);
}
int main()
{
	LinkList L;
	int length;
	cin >> length;
	findmin(L, length);
	system("pause");
	return 0;
}

05.将带头结点的单链表就地逆置

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L)
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void TailForm(LinkList &L, int length) // 尾插法建立链表 
{
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void reverse(LinkList &L, int length)
{
	TailForm(L, length);
	LNode * p = L -> next;
	L -> next = NULL; 
	while(p != NULL)
	{
		LNode * s = p -> next;
		p -> next = L -> next;
		L -> next = p;
		p = s;
	}
	Output(L);
}
int main()
{
	LinkList L;
	int length;
	cin >> length;
	reverse(L, length); 
	system("pause");
	return 0;
}

06.设计算法使带头结点的单链表递增有序

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L)
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void TailForm(LinkList &L, int length) // 尾插法建立链表 
{
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void swap(LNode * &p, LNode * &q)
{
	int temp = q -> data;
	q -> data = p -> data;
	p -> data = temp;
}
void bubble(LinkList &L)
{
	LNode * p = L -> next;
	LNode * q;
	while(p != NULL)
	{
		q = p -> next;
		while(q != NULL)
		{
			if(p -> data > q -> data)
				swap(p, q);
			q = q -> next;
		}
		p = p -> next;
	}
}
int main()
{
	LinkList L;
	int length;
	cin >> length;
	TailForm(L, length);
	bubble(L);
	Output(L);
	system("pause");
	return 0;
}

07.删除无序单链表中介于给定两个值之间的元素的元素

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void Del(LinkList &L, int x, int y)
{
	LNode * p = L -> next;
	LNode * prev = L;
	while(p != NULL)
	{
		if (p->data >= x && p->data <= y)
        {
            LNode *temp = p;
            prev -> next = p -> next;
            p = p -> next;
            delete temp;
        }
        else
        {
            prev = p;   
            p = p -> next;
        }
	}
}
int main()
{
	LinkList L;
	TailForm(L);
	int x, y;
	cout << "请输入要删除的元素的范围：" << endl;
	cin >> x >> y;
	Del(L, x, y);
	Output(L);
	system("pause");
	return 0;
}

08.找出两个链表的公共结点

//时间复杂度：O(len1 + len2) 
#include
#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
int len(LinkList L)
{
	LNode * p = L -> next;
	int count = 0;
	while(p != NULL)
	{
		count ++;
		p = p -> next;
	}
	return count;
}
LNode * Node(LinkList L1, LinkList L2)
{
	int lenn = len(L1) - len(L2);
	LNode * p, * q;
	int i = 0, x;
	if(lenn > 0)
	{
		x = len(L2);
		p = L1 -> next;
		while(i <= lenn)
		{
			p = p -> next;
			i ++;
		}
		q = L2 -> next;
	}
	else
	{
		x = len(L1);
		p = L2 -> next;
		while(i <= abs(lenn))
		{
			p = p -> next;
			i ++;
		}
		q = L1 -> next;
	}
	i = 0;
	while(i <= x)
	{
		if (p == q)
			return p;
		p = p -> next;
		q = q -> next;
		i++;
	}
	return NULL;
}
int main()
{
	LinkList L1, L2;
	TailForm(L1);
	TailForm(L2);
	LNode * p = Node(L1, L2);
	system("pause");
	return 0;
}

09.

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void swap(LNode * &p, LNode * &q)
{
	int temp = q -> data;
	q -> data = p -> data;
	p -> data = temp;
}
void bubble(LinkList &L)
{
	LNode * p = L -> next;
	LNode * q;
	while(p != NULL)
	{
		q = p -> next;
		while(q != NULL)
		{
			if(p -> data > q -> data)
				swap(p, q);
			q = q -> next;
		}
		p = p -> next;
	}
	p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		q = p -> next;
		L -> next = q;
		delete(p);
		p = q;
	}
}
int main()
{
	LinkList L;
	TailForm(L);
	bubble(L);
	system("pause");
	return 0;
}

10. 

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void devide(LinkList &A, LinkList &B)
{
	InitLinkList(B);
	LNode * p = A -> next;
	LNode * pre = A;
	LNode * q = B;
	while(p != NULL)
	{
		if(p -> data % 2 == 0)
		{
			LNode * s = new LNode;
			s -> data = p -> data;
			s -> next = q -> next;
			q -> next = s;
			q = s;
			LNode * n = p -> next;
			pre -> next = n;
			delete(p);
			p = n;
		}
		else
		{
			p = p -> next;
			pre = pre -> next;
		}
	}
}
int main()
{
	LinkList L, B;
	TailForm(L);
	devide(L, B);
	cout << "奇数：" << endl;
	Output(L);
	cout << "偶数：" << endl;
	Output(B);
	system("pause");
	return 0;
}

11.

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void devide(LinkList &A, LinkList &B)
{
	InitLinkList(B);
	LNode * p = A -> next;
	LNode * pre = A;
	int i = 1;
	while(p != NULL)
	{
		if(i % 2 == 0)
		{
			LNode * s = new LNode;
			s -> data = p -> data;
			s -> next = B -> next;
			B -> next = s;
			LNode * n = p -> next;
			pre -> next = n;
			delete(p);
			p = n;
		}
		else
		{
			p = p -> next;
			pre = pre -> next;
		}
		i++;
	}	
}
int main()
{
	LinkList L, B;
	TailForm(L);
	devide(L, B);
	Output(L);
	Output(B);
	system("pause");
	return 0;
}

12.

#include
using namespace std;
#define maxnum 0x7fffffff
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void del(LinkList &L)
{
	L -> data = maxnum;
	LNode * p = L -> next;
	LNode * pre = L;
	while(p != NULL)
	{
		if(p -> data == pre -> data)
		{
			LNode * s = p -> next;
			pre -> next = s;
			delete(p);
			p = s;
		}
		else
		{
			pre = p;
			p = p -> next;
		}
	}
}
int main()
{
	LinkList L;
	TailForm(L);
	del(L);
	Output(L);
	system("pause");
	return 0;
}

13.

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void add(LinkList &A, LinkList &B)
{
	LNode * p1 = A -> next;
	A -> next = NULL;
	LNode * p2 = B -> next;
	LNode * p;
	while(p1 != NULL && p2 != NULL)
	{
		if(p1 -> data < p2 -> data)
		{
			p = p1 -> next;
			p1 -> next = A -> next;
			A -> next = p1;
			p1 = p;
		}
		else
		{
			p = p2 -> next;
			p2 -> next = A -> next;
			A -> next = p2;
			p2 = p;
		}
	}
	while(p1 != NULL)
	{
		p = p1 -> next;
		p1 -> next = A -> next;
		A -> next = p1;
		p1 = p;
	}
	while(p2 != NULL)
	{
		p = p2 -> next;
		p2 -> next = A -> next;
		A -> next = p2;
		p2 = p;
	}
}
int main()
{
	LinkList L, B;
	TailForm(L);
	TailForm(B);
	add(L, B);
	Output(L);
	system("pause");
	return 0;
}

14.

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
LinkList add(LinkList &A, LinkList &B)
{
	LinkList C;
	InitLinkList(C);
	LNode * a = A -> next;
	LNode * b = B -> next;
	LNode * p = C, * s;
	while(a != NULL && b != NULL)
	{
		if(a -> data > b -> data)
			b = b -> next;
		else if(a -> data < b -> data)
			a = a -> next;
		else
		{
			s = new LNode;
			s -> data = a -> data;
			p -> next = s;
			p = s; 
			a = a -> next;
		}
	}
	p -> next = NULL;
	return C;
}
int main()
{
	LinkList A, B;
	TailForm(A);
	TailForm(B);
	LinkList C = add(A, B);
	Output(C);
	system("pause");
	return 0;
}

15.

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void add(LinkList &A, LinkList &B)
{
	LNode * a = A -> next;
	A -> next = NULL; 
	LNode * b = B -> next;
	LNode * p = A, * s;
	while(a != NULL && b != NULL)
	{
		if(a -> data > b -> data)
			b = b -> next;
		else if(a -> data < b -> data)
			a = a -> next;
		else
		{
			s = new LNode;
			s -> data = a -> data;
			p -> next = s;
			p = s; 
			a = a -> next;
		}
	}
	p -> next = NULL;
}
int main()
{
	LinkList A, B;
	TailForm(A);
	TailForm(B);
	add(A, B);
	Output(A);
	system("pause");
	return 0;
}

16.

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
bool IfIs(LinkList &A, LinkList &B)
{
	LNode * a = A -> next;
	LNode * b = B -> next;
	while(a)
	{
		LNode * aa = a;
		LNode * bb = b;
		if(a -> data == b -> data)
		{
			bool flag = true;
			while(a && b)
			{
				if(a -> data != b -> data)
				{
					flag = false;
					break;
				}
				a = a -> next;
				b = b -> next;
			}
			if(flag)
				return true;
			a = aa;
			b = bb;
		}
		a = a -> next;
	}
	return false;
}
int main()
{
	LinkList A, B;
	TailForm(A);
	TailForm(B);
	if(IfIs(A, B))
		cout << "yes!" << endl;
	else
		cout << "no!!!" << endl;
	system("pause");
	return 0;
}

17.

#include
using namespace std;
typedef struct DNode{
	DNode * next;
	DNode * prior;
	int data;
}DNode, * DLinkList;
bool InitDLinkList(DLinkList &L) // 初始化一个循环双链表 
{
	L = new DNode;
	if (L == NULL)
		return false;
	L -> next = L;
	L -> prior = L;
	return true;
}
void TailForm(DLinkList &L) // 尾插法 
{
	InitDLinkList(L);
	int length, i = 1;
	cout << "请输入链表长度：" << endl;
	cin >> length;
	DNode * p = L;
	int x;
	cout << "链表初始数据: " << endl;
	while(i <= length)
	{
		DNode * s = new DNode;
		cin >> x;
		s -> data = x;
		p -> next = s;
		s -> prior = p;
		p = s; 
		i ++;
	}
	p -> next = L;
	L -> prior = p;
} 
void output(DLinkList L) // 输出 
{
	DNode * p = L -> next;
	cout << "输出：" << endl;
	while(p != L)
	{
		cout << p -> data << " ";
		p = p -> next; 
	}
	cout << endl;
}
bool IF(DLinkList L)
{
	DNode * p = L;
	DNode * q = L;
	while(p -> next != q)
	{
		if(p == q && p != L)
			break;
		p = p -> next;
		q = q -> prior;
		if(p -> data != q -> data)
			return false;
	}
	return true;
}
int main()
{
	DLinkList L;
	TailForm(L);
	if(IF(L))
		cout << "yes" << endl;
	else
		cout << "no" << endl;
	system("pause");
	return 0;
}

18.

#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = L;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != L)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = L;
}
void add(LinkList &A, LinkList &B)
{
	LNode * r1 = A;
	LNode * r2 = B; 
	while(r1 -> next != A)
		r1 = r1 -> next;
	while(r2 -> next != B)
		r2 = r2 -> next;
	r1 -> next = B;
	B -> data = 520;
	r2 -> next = A; 
}
int main()
{
	LinkList A, B;
	TailForm(A);
	TailForm(B);
	add(A, B);
	Output(A);
	system("pause");
	return 0; 
}

19.

#include
using namespace std;
#define maxnum 0x7fffffff
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的循环单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = L;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的循环单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != L)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立循环单链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = L;
}
void putmin(LinkList &L)
{
	L -> data = maxnum;
	while(L -> next != L)
	{
		LNode * p = L -> next;
		LNode * pre = L;
		LNode * minp = L -> next;
		LNode * minpre = L;
		while(p != L)
		{
			if(p -> data < minp -> data)
			{
				minp = p;
				minpre = pre;
			}
			pre = p;
			p = p -> next;
		}
		cout << minp -> data << " ";
		minpre -> next = minp -> next;
		delete(minp);
	}
	cout << endl;
	delete(L);
} 
int main()
{
	LinkList L;
	TailForm(L);
	putmin(L);
	system("pause");
	return 0;
}

20.

#include
using namespace std;
typedef struct DNode{ // 非循环双链表结构体 

	DNode * pre;
	DNode * next;
	int data;
	int freq;
}DNode, * DLinkList;
bool InitList(DLinkList &L) //初始化一个非循环双链表 
{
	L = new DNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	L -> pre = NULL;
	return true;
}
void TailForm(DLinkList &L) // 尾插法建立非循环双链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitList(L); 
	int i = 1, x;
	DNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		DNode * s = new DNode;
		s -> data = x;
		s -> freq = 0;
		p -> next = s;
		s -> pre = p;
		p = s;
		i++;
	}
	p -> next = NULL;
} 
void output(DLinkList L) // 输出非循环双链表 
{
	DNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
	p = L -> next;
	while(p != NULL)
	{
		cout << p -> freq << " ";
		p = p -> next;
	}
	cout << endl;
}
void swap(DNode * p, DNode * q) // 交换两个节点 
{
	if(p == q)
		return;
	DNode * s = q -> pre;
	if(p -> next == NULL)
	{
		s -> next = p;
		p -> pre = s;
		q -> next = NULL;
		q -> pre = p;
		p -> next = q;  
		return;
	}
	DNode * r = p -> next;
	s -> next = p;
	p -> pre = s;
	r -> pre = q;
	q -> next = r;
	p -> next = q;
	q -> pre = p;
}
void Locate(DLinkList &L, int x) // 目标函数 
{
	DNode * p = L -> next;
	while(p != NULL)
	{
		if (p -> data == x)
        {
            p -> freq++;
            DNode * q = p -> pre;
            while (q != L && p -> freq >= q -> freq)
            {
                swap(p, q);
                q = p -> pre;
            }
            break;
        }
		p = p -> next;
	}
}
int main()
{
	DLinkList L;
	TailForm(L);
	int x;
	cout << "输入要调用的数据: " << endl;
	while(cin >> x)
	{
		Locate(L, x);
		output(L);
	}
	system("pause");
	return 0;
}

21.

/*
一. 先遍历链表，找到尾指针，存下尾指针的后继节点，记为point 
	再遍历链表，与point作对比，若相等则返回true
	否则返回false 
二. 弗洛伊德判圈法 
*/
#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool hasCycle(LinkList L) // 弗洛伊德判圈法
{
	LNode * slow = L;
	LNode * fast = L;
	if(L -> next == NULL || L == NULL)
		return false;
	while(fast != NULL && fast -> next != NULL)
	{
		slow = slow -> next;
		fast = fast -> next -> next;
		if(fast == slow)
			return true;
	}
	return false;
}
/*
时间复杂度：O(n)
空间复杂度：O(1) 
*/

22.

/*
先找两个指针指向L -> next
先让p向后移动k个距离，再让p与q一起移动，直至p指向尾指针
此时q所指向的就是倒数第k个结点 
*/
#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1, x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
int findk(LinkList L, int k)
{
	LNode * p = L -> next;
	LNode * q = L -> next;
	int i = 1;
	while(i < k && p != NULL)
	{
		p = p -> next;
		i ++;
	}
	if(i < k || p == NULL)
		return 0;
	while(p -> next != NULL)
	{
		p = p -> next;
		q = q -> next;
	}	
	cout << q -> data << endl;
	return 1; 
} 
int main()
{
	LinkList L;
	TailForm(L);
	int k;
	cout << "请输入欲得到的倒数第k个结点：" << endl;
	cin >> k;
	findk(L, k);
	system("pause");
	return 0;
}
/*
时间复杂度：O(n)
空间复杂度: O(1) 
*/

23.

/*
	先求出两个链表的长度
	让长度长的链表的指针先向后移动
	再同步向后移动 
*/
#include
#include
using namespace std;
typedef struct LNode{
	LNode * next;
	char data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1;
	char x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
int length(LinkList L)
{
	LNode * p = L -> next;
	int i = 0;
	while(p != NULL)
	{
		p = p -> next;
		i ++;
	}
	return i;
}
LNode * After(LinkList A, LinkList B)
{
	LNode * p = A -> next, * q = B -> next;
	int lena = length(A), lenb = length(B);
	int i = 1;
	if(lena >= lenb)
		while(i <= lena - lenb)
		{
			p = p -> next;
			i ++;
		}
	else
		while(i <= lenb - lena)
		{
			q = q -> next;
			i ++;
		}
	while(p != NULL)
	{
		if(p -> data == q -> data)
			break;
		p = p -> next;
		q = q -> next;
	}
	return p;
}
int main()
{
	LinkList A, B;
	TailForm(A);
	TailForm(B);
	LNode * p = After(A, B);
	cout << p -> data << endl;
	system("pause");
	return 0;
}
/*
时间复杂度：O(lena + lenb)
空间复杂度：O(1) 
*/

24.

/*
用空间换时间
定义计数数组 
*/
#include
#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode, * LinkList;
bool InitLinkList(LinkList &L) // 初始化一个带头结点的单链表 
{
	L = new LNode;
	if(L == NULL)
		return false;
	L -> next = NULL;
	return true;
}
void Output(LinkList L) // 输出一个带头结点的单链表中所有的值 
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
void TailForm(LinkList &L) // 尾插法建立链表 
{
	int length;
	cout << "请输入链表初始长度：" << endl; 
	cin >> length;
	InitLinkList(L); 
	int i = 1;
	int x;
	LNode * p = L; 
	cout << "请输入链表中的初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		p -> next = s;
		p = s;
		i++; 
	}
	p -> next = NULL;
}
void function(LinkList &L, int * count, int n)
{
	int i;
	for(i = 0; i < n + 1; i++)
		count[i] = 0;
	LNode * p = L -> next;
	LNode * pre = L;
	while(p != NULL)
	{
		if(count[abs(p->data)] == 0)
		{
			count[abs(p->data)] ++;
			pre = p;
			p = p -> next;
		}
		else
		{
			pre -> next = p -> next;
			delete(p);
			p = pre -> next;
		}
		
	}
}
int main()
{
	LinkList L;
	int n;
	cout << "请输入数组的最大值：" << endl; 
	cin >> n;
	int count[n + 1];
	TailForm(L);
	function(L, count, n);
	Output(L);
	system("pause");
	return 0;
}
/*
时间复杂度：O(max(n, length))
空间复杂度： O(n)
*/

25.

/*
先找到单链表的中间结点r
将单链表后半段就地逆置
以r为工作指针将结点插入相应的位置 
*/
#include
using namespace std;
typedef struct LNode{
	LNode * next;
	int data;
}LNode;
void TailForm(LNode * &L)
{
	L = new LNode;
	if(L == NULL)
		return;
	L -> next = NULL;
	cout << "请输入链表初始长度:" << endl;
	int length;
	cin >> length; 
	int x, i = 1;
	LNode * p = L;
	cout << "链表初始元素：" << endl;
	while(i <= length)
	{
		cin >> x;
		LNode * s = new LNode;
		s -> data = x;
		s -> next = p -> next;
		p -> next = s;
		p = s;
		i++;
	}
	p -> next = NULL;
}
void output(LNode * L)
{
	LNode * p = L -> next;
	while(p != NULL)
	{
		cout << p -> data << " ";
		p = p -> next;
	}
	cout << endl;
}
int len(LNode * L)
{
	int i = 1;
	LNode * p = L->next;
	while(p != NULL)
	{
		p = p->next;
		i++;
	} 
	return i;
}
void function(LNode * &L)
{
	LNode * p = L->next;
	LNode * r = L->next;
	if(p->next == NULL)
		return;
	LNode * rpre = L;
	int length = len(L);
	int i = 1, l = length / 2;
	if(length % 2 == 0)
		while(i < l + 1)
		{
			rpre = rpre->next;
			r = r->next;
			i++;
		}
	else
		while(i <= l + 1)
		{
			rpre = rpre->next;
			r = r->next;
			i++;
		}
	rpre->next = NULL;
	while(r != NULL)
	{
		LNode * link = r -> next;
		r->next = rpre->next;
		rpre->next = r;
		r = link;
	}
	r = rpre->next;
	LNode * q = p->next;
	while(r != NULL)
	{
		rpre->next = r->next;
		r->next = p->next;
		p->next = r;
		p = q;
		q = q->next;
		r = rpre->next;
	}
}
int main()
{
	LNode * L;
	TailForm(L);
	function(L);
	output(L);
	system("pause");
	return 0;
}
/*
时间复杂度：O(n)
空间复杂度：O(1)
*/