与分析——描述 第三章的单链表

很基础的东西。走一遍流程。有人说学编程最简单最笨的方法就是把书上的代码敲一遍。这个我是头文件是照抄的。.c源文件自己实现。

 

 

list.h

 

typedef int ElementType;
#ifndef _List_H
#define _List_H

struct Node;
typedef struct Node *PtrToNode;
typedef PtrToNode List;
typedef PtrToNode Position;

List CreatList();
List MakeEmpty(List L);
int IsEmpty(List L);
int IsLast(Position P, List L);
Position Find(ElementType X, List L);
void Delete(ElementType X, List L);
Position FindPrevious(ElementType X, List L);
void Insert(ElementType X, Position P);
void DeleteList(List L);
Position Header(List L);
Position First(List L);
Position Advance(Position P);
ElementType Retrieve(Position P);

#endif

 

 

list.c

 

#include"list.h"
#include<stdlib.h>
#include"fatal.h"

struct  Node
{
    ElementType Element;
    Position Next;
};

List CreatList() {
    List l = malloc(sizeof(struct Node));
    if (l == NULL)
        Error("out of memory");
    l->Next = NULL;
    return l;
}

List MakeEmpty(List L) {
    if (L != NULL)
        DeleteList(L);
    L = malloc(sizeof(struct Node));
    if (L == NULL)
        FatalError("Out of memory");
    L->Next = NULL;
    return L;
}

int IsEmpty(List L) {
    return L->Next == NULL;
}

int IsLast(Position P, List L) {
    return P->Next == NULL;
}

Position Find(ElementType X, List L) {
    Position P;
    P = L->Next;
    while (P != NULL&&P->Element != X)
    {
        P = P->Next;
    }
    return P;
}

void Delete(ElementType X, List L) {
    Position P;
    P = FindPrevious(X, L);
    if (!IsLast(P, L)) {
        Position TmpCell = P->Next;
        P->Next = TmpCell->Next;
        free(TmpCell);
    }
}

Position FindPrevious(ElementType X, List L) {
    Position P;
    P = L;
    while (P->Next != NULL&&P->Next->Element != X)
        P = P->Next;
    return P;
}

void Insert(ElementType X, Position P) {
    Position tmpCell;
    tmpCell = malloc(sizeof(struct Node));
    if (tmpCell == NULL)
        FatalError("Out of space!!");
    tmpCell->Element = X;
    tmpCell->Next = P->Next;
    P->Next = tmpCell;
}

void DeleteList(List L) {
    Position p;
    p = L->Next;
    L->Next = NULL;
    while (p != NULL){
        Position tmp;
        tmp = p->Next;
        free(p);
        p = tmp;
    }
}

Position Header(List L) {
    return L;
}

Position First(List L) {
    return L->Next;
}

Position Advance(Position P) {
    return P->Next;
}

ElementType Retrieve(Position P) {
    return P->Element;
}

 

fatal.h

 

               #include<stdio.h>          #include<stdlib.h>                    #define Error(Str) FatalError(Str)          #define FatalError(Str) fprintf(stderr,"%s\n",Str),exit(1)
#include<stdio.h>
#include<stdlib.h>

#define Error(Str) FatalError(Str)
#define FatalError(Str) fprintf(stderr,"%s\n",Str),exit(1)