#include "math.h"
#include "stdlib.h" //exit()
typedef int DataType;
#include "malloc.h" //malloc()
typedef struct Node
{
DataType data;
struct Node *next;
} SLNode;
void ListInitiate(SLNode **head)
{
if ((*head = (SLNode *)malloc(sizeof(SLNode))) == NULL) exit(1);
(*head)->next = NULL;
}
//在带头节点的单链表head的第i（0<=i<=size）个结点前插入
int ListInsert(SLNode * head, int i, DataType x)
{
SLNode *p, *q;
int j;
p = head;
j = -1;
//其实就是i-1-(-1)=i次，把p指针移到第i-1个结点上,因为结点从0开始
while (p->next != NULL && j < i - 1)
{
p = p->next;
j++;
}
if (j != i - 1)
{
printf("insert error !/n");
return 0;
}
if ((q = (SLNode *)malloc(sizeof(SLNode))) == NULL) exit(1);
q->data = x;
q->next = p->next;
p->next = q;
return 1;
}
//释放动态申请的内存空间
void Destroy(SLNode * *head)
{
SLNode *p, *p1;
p = *head;
while (p != NULL)
{
p1 = p;
p = p->next;
free(p1);
}
*head = NULL;
}
void Buildloop(SLNode *head, SLNode *head2, DataType m, DataType n)
{
int flag1 = 0, flag2 = 0;
SLNode *p, *q, *r, *s;
p = head->next;
q = head2;
while (p != NULL)
{
if (p->data ==m ) {
flag1++;
if (flag1 == 1) {
r = (SLNode *)malloc(sizeof(SLNode));
r->data = m;
r->next = p->next;
}
}
if (p->data == n) {
flag2++;
if (flag2 == 1) {
s = (SLNode *)malloc(sizeof(SLNode));
s->data = n;
s->next = p->next;
//s = p;
}
if (flag1 == 1 && flag2 == 1)
break;
}
/*if (s->next = NULL) {
s->next = r;
}*/
head2->next = s->next;
s->next = r;
while (q->next != NULL) {
q = q->next;
}
q->next = r;
}
}
int FindLoopNode(SLNode *head, int j)
{
int i = j, begin = 1;
SLNode *fast = head, *slow = head;
for (i; i > 0; i--) {
fast = fast->next;
}
slow = head;
while (slow != fast) {
begin++;
slow = slow->next;
fast = fast->next;
}
return begin;
}
int IsExitsloop(SLNode *head)
{
SLNode *slow = head;
SLNode *fast = head;
int i, j = 1;
while (fast&&fast->next)
{
slow = slow->next;
fast = fast->next->next;
if (slow == fast)break;
}
if (fast == NULL || fast->next == NULL) {
printf("该链表不存在环！\n");
}
else {
printf("该链表存在环！\n");
while (fast&&fast->next) {
slow = slow->next;//fast与slow相遇后，slow并没有遍历完链表，继续遍历
j++;
if (slow->next == fast)break;
}
}
i = FindLoopNode(head, j);
printf("环的起始位置为:%d\n", i);
printf("环的结束位置为:%d\n", j + i - 1);
return 0;
}
int ListLength(SLNode *head)
{
SLNode *slow = head->next, *fast = head->next;
int length = 1;
while (fast&&fast->next) {
slow = slow->next;
fast = fast->next->next;
if (slow == fast)
{
while (fast&&fast->next)
{
slow = slow->next;
length++;
if (slow->next == fast)break;
}
break;
}
}
return length;
}
void ReList(SLNode *head)
{
SLNode *p = head, *q = head;
int length = ListLength(head);
for (; length > 0; length--)p = p->next;
while (p != q)
{
q = q->next;
if (p->next == q)
{
p->next = NULL;
break;
}
p = p->next;
}
}
void IsIntersect(SLNode *head, SLNode *head2)
{
SLNode *p, *q;
p = head;
q = head2;
int i = 0, flag = 0;
while (p->next != NULL)
{
i++;
p = p->next;
while (q->next != NULL)
{
q = q->next;
if (p == q) {
flag = 1;
printf("链表存在相交位置，位置为%d\n",i);
break;
}
}
if (flag == 1)break;
}
if (flag != 1)
printf("链表不相交！");
}
#pragma once
