单向链表的一些操作

#include <stdio.h>#include <malloc.h>#include <stdlib.h>//声明枚举类型，linux下C语言没有bool类型typedef enum bool{false = 0,true = 1}bool;typedef struct Node{int data;//数据域struct Node* pNext;//指针域}NODE, *PNODE;//NODE等价于 struct Node， PNODE等价于struct Node*//函数声明部分PNODE createList();//分配内存创建listvoid traverseList(PNODE pHead);//遍历listbool isEmpty(PNODE pHead);//判断是否为空bool insertList(PNODE, int, int);//插入数据，postion从1开始bool deleteList(PNODE, int, int*);//删除数据int lengthList(PNODE pHead);//返回长度void sortList(PNODE pHead);//排序int main(){PNODE pHead = NULL;//struct Node *pHead = NULL；int count = 0;//链表长度int delvalue;//要删除数据pHead = createList();//创建一个非循环单链表，并将该链表的头结点地址赋给pHeadtraverseList(pHead);//遍历listif(isEmpty(pHead))printf("链表为空！\n");elseprintf("链表不为空\n");sortList(pHead);traverseList(pHead);insertList(pHead,2,100);traverseList(pHead);count = lengthList(pHead);printf("链表长度是：%d\n",count);if(deleteList(pHead,2,&delvalue))printf("删除成功，删除的元素是：%d\n",delvalue);elseprintf("删除失败！\n");traverseList(pHead);count = lengthList(pHead);printf("链表长度是：%d\n",count);return 0;}bool deleteList(PNODE pHead, int postion, int* delValue)//删除数据{int i = 0;PNODE p = pHead;//使 p指向 postion 前面的一个结点 while(p->pNext != NULL && i< postion - 1){p = p->pNext;++i;}if(i > postion - 1 || p->pNext == NULL)return false;//删除操作PNODE q = p->pNext;*delValue = q->data;//删除p结点后面的结点p->pNext = p->pNext->pNext;free(q);return true;}//在pHead所指向链表的第postion个结点的前面插入一个新的结点,该结点的值是value//并且postion从1开始bool insertList(PNODE pHead, int postion, int value )//插入数据{int i = 0;PNODE p = pHead;//使 p指向 postion 前面的一个结点 while(p != NULL && i< postion - 1){p = p->pNext;++i;}if(i > postion - 1 || p == NULL)return false;PNODE pNew = (PNODE)malloc(sizeof(NODE));if(pNew == NULL){printf("动态分配内存失败！\n");exit(-1);}pNew->data = value;PNODE q = p->pNext;p->pNext = pNew;pNew->pNext = q;return true;}void sortList(PNODE pHead)//排序{int temp,j,i;int length = lengthList(pHead);PNODE p,q;for(i = 0,p = pHead->pNext; i< length - 1;++i,p = p->pNext){for(j = i+1,q = p->pNext; j< length; ++j,q = q->pNext){if(p->data > q->data){temp = p->data;p->data = q->data;q->data = temp;}}}}int lengthList(PNODE pHead)//返回长度{PNODE p = pHead->pNext;int count = 0;//计数while(p != NULL){++count;p = p->pNext;}return count;}bool isEmpty(PNODE pHead)//判断是否为空{//头结点的指针域为空则链表为空if(pHead->pNext == NULL)return true;elsereturn false;}PNODE createList()   //create list and storage alloction {int length;   //存放有效结点的个数int i;int value;//临时存放用户输入的结点的值//分配了一个不存放有效数据的头结点PNODE pHead = (PNODE)malloc(sizeof(NODE));if(pHead == NULL){printf("分配失败，程序终止！\n");exit(-1);}//假定pTail永远指向尾节点PNODE pTail = pHead;pTail->pNext = NULL;printf("请输入要生成结点的个数：length = ");scanf("%d",&length);for(i = 0; i< length; ++i){printf("请输入 %d 个结点的值：",i+1);scanf("%d",&value);PNODE pNew = (PNODE)malloc(sizeof(NODE));if(pNew == NULL){printf("分配失败,程序终止！\n");exit(-1);}pNew->data = value;pTail->pNext = pNew;pNew->pNext = NULL;pTail = pNew;}return pHead;}void traverseList(PNODE pHead)  //traverse list ,遍历链表不能用下标，因为链表不是数组{PNODE p = pHead->pNext;//当指针p指向的不为空一直输出while(p != NULL){printf("%d ",p->data);p = p->pNext;}printf("\n");}//createList();函数给链表动态分配内存//1.example： //int i = 10;//int *p = (int *)malloc(100);//解释：int i = 10；是临时分配的局部变量，函数调用完内存就会释放//而用malloc申请的内存在函数调用完后，指针p会释放但是申请的100字节的内存不会释放。//2.method：//可以再一个函数中分配内存然后在别的主调函数中使用