单链表的函数声明和定义

#include<stdio.h>#include<stdlib.h>typedef int ElemType;typedef struct node {ElemType data;struct node *next;}Node;typedef Node* PtrToNode;typedef PtrToNode List;typedef PtrToNode Position;//判断是否是空链表int IsEmpty(List L) {return L->next == NULL;}//判断是否是末尾int IsLast(Position P, List L) {return P->next == NULL;}//寻找Position Find(ElemType X, List L) {Position P;P = L->next;while (P != NULL && P->data != X) {P = P->next;}return P;}Position FindPrevious(ElemType X, List L) {Position P;P = L;while (P->next != NULL && P->next->data != X) {P = P->next;}return P;}void Delete(ElemType X, List L) {Position P, Tmp;P = FindPrevious(X, L);if (!IsLast(P,L)) {Tmp = P->next;P->next = Tmp;free(Tmp);}}//根据位置来插入元素  void InSert(ElemType X, List L, Position P) {Position TmpCell;TmpCell = (List)malloc(sizeof(Node));if (TmpCell == NULL) {printf("Out of space!!!");}TmpCell->data = X;TmpCell->next = P->next;P->next = TmpCell;}//输出链表  void PrintList(List L) {Position P;P = L;while (P != NULL) {printf("%d ", P->data);P = P->next;}printf("\n");}//创建链表  List CreatedList() {Position head, p1, p2;int n;p2 = p1 = (Node*)malloc(sizeof(Node));if (p1 == NULL) {printf("Can not create p1!!!");return NULL;}else {head = NULL;n = 0;printf("请输入数据：");scanf_s("%d", &(p1->data));while (p1->data != 0) {n++;if (n == 1) {head = p1;p2->next = NULL;}else {p2->next = p1;}p2 = p1;p1 = (struct node*)malloc(sizeof(struct node));printf("请输入数据：");scanf_s("%d", &(p1->data));}p2->next = NULL;free(p1);p1 = NULL;return head;}}//删除链表  void DeLeteList(List L) {Position P, Tmp;P = L->next;L->next = NULL;while (P != NULL) {Tmp = P->next;free(P);P = Tmp;}}//生成空链表  List MakeEmpty(List L) {L = (struct node*)malloc(sizeof(struct node));L->data = 0;L->next = NULL;return L;}//返回头结点  Position Header(List L) {return L;}//返回第一个数据节点的位置  Position First(List L) {if (L->next != NULL)return L->next;}//获得位置P后继节点位置  Position Advance(Position P) {if (P != NULL)return P->next;}//返回P位置的数据  ElemType Retrieve(Position P) {if (P != NULL)return P->data;}