鏈表的遊標實現

//Cursor.h
#ifndef _CURSOR_H_

typedef int PtrNode;
typedef PtrNode List;
typedef PtrNode Position;
typedef PtrNode ElementType; 
#define SpaceSize 30

struct Node
{
	ElementType Element;
	Position Next;
};

struct Node CursorSpace[SpaceSize];

void InitializeCursorSpace(int N);
Position CursorAlloc(void);
static void CursorFree(Position P);
int IsEmpty(List L);
int IsLast(Position P,List L);
Position Find(ElementType X,List L);
Position FindPrevious(ElementType X,List L);
void Delete(ElementType X,List L);
void Insert(ElementType X,List L,Position P);
void print_CursorSpace(List L);


#endif 

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//Cursor.c
#include<stdio.h>
#include "Cursor.h"
#include<stdlib.h>

void InitializeCursorSpace(int N)       //初始化用來裝結構體元素的N個空節點
{
	
	int i;
	for(i=0;i<N-1;i++)
	{
		CursorSpace[i].Next=i+1; 
	}
	CursorSpace[i].Next=0;
} 
Position CursorAlloc(void)
{
	Position P;
	P=CursorSpace[0].Next;
	CursorSpace[0].Next=CursorSpace[P].Next;                 //實現malloc功能 
	
	return P; 
}

static void Cursorfree(Position P)
{
	CursorSpace[P].Next=CursorSpace[0].Next;                //實現free功能 
	CursorSpace[0].Next=P;
}

int IsEmpty(List L)
{
	return !CursorSpace[L].Next;
}

int IsLast(Position P,List L)
{
	return !CursorSpace[P].Next;
}

Position Find(ElementType X,List L)
{
	Position p;
	p=CursorSpace[L].Next;
	while(p&&(CursorSpace[p].Element!=X))
	{
		p=CursorSpace[p].Next;
	}
	
	return p;
}

Position FindPrevious(ElementType X,List L)
{
	Position p;
	p=L;
	while((CursorSpace[p].Next)&&(CursorSpace[CursorSpace[p].Next].Element!=X))
	{
		p=CursorSpace[p].Next;
	}
	if(CursorSpace[p].Next==0)
	{                                        //找到了返回p值，不然返回0 
		return 0;
	}
	else
	{
		return p;
	}
}

void Delete(ElementType X,List L)
{
	Position p,q;
	p=FindPrevious(X,L);
	if(p==0)
	{
		printf("Please check your input for correct---X!");
		return;
	}
	else
	{
		q=CursorSpace[p].Next;
		CursorSpace[p].Next=CursorSpace[q].Next;
		Cursorfree(q);
	}
}

void Insert(ElementType X,List L,Position P)   //後插 
{
	Position q;
	q=CursorAlloc();
	if(q==0)
	{
		printf("out of space\n");
	}
	CursorSpace[q].Element=X;
	CursorSpace[q].Next=CursorSpace[P].Next;
	CursorSpace[P].Next=q;
} 

void print_CursorSpace(List L)
{
	List p;
	p=L;
	while(CursorSpace[p].Next!=0)
	{
		p=CursorSpace[p].Next;
		printf("%d\n",CursorSpace[p].Element);
	}
	//printf("%d\n",CursorSpace[L].Element);
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//main.c
#include<stdio.h>
#include "Cursor.h"

//void init_cursor(List )
int main(void)
{
	int i;
	for(i=0;i<SpaceSize-1;i++)
	{
		CursorSpace[i].Next=i+1;
	}
	CursorSpace[i].Next=0;
	
	Position L;
	L=CursorAlloc();            //得到一個頭節點heard
	CursorSpace[L].Next=0;
	
	printf("請輸入數據存入遊標鏈表中:\n");
	int q;
	int j=1;
	scanf("%d",&q); 
	
	if(q!=99)
		{
			Insert(q,L,L);//後插 
		}
		else
		{
			return;
		}
		
	while(!(q==99)&&(j<10))
	{
		List p;
		p=CursorAlloc();
		printf("請輸入數據存入遊標鏈表中:\n");
		scanf("%d",&q);
		if(q!=99)
		{
			Insert(q,L,L);//後插 
		}
		else
		{
			printf("------------------------\n");
		}
		
		
		
		
	}
	print_CursorSpace(L);
}