数据结构与算法学习笔记——链表部分实现（数组形式）

/******************************************************************************************************* Copyright(C);* Filename    :* Author      :* Version     :* Date        :* Description :******************************************************************************************************/#include <stdio.h>/****************************************************************/#define ElementType   unsigned int#define MAX_ELEMENT    10#define NIL  -1int _L, _F;ElementType  _key[ MAX_ELEMENT+1 ];ElementType _next[ MAX_ELEMENT+1 ];ElementType _prev[ MAX_ELEMENT+1 ];/****************************************************************/int  AllocateObject	(void);void CreateList		(void);int  Delete         (int pos);int  Find           (ElementType e );void FreeObject     (int pos);int  GetLength      (void);int  Insert         (ElementType e, int pos);int  IsEmpty		(void);int  IsFull			(void);int  IsLast			(int pos);void ListIndex      (void);void PrintList      (void);/****************************************************************/int main(void){int i;CreateList();for ( i=0; i<MAX_ELEMENT; i++ ){Insert(i,i);}printf("length:%d\n",GetLength());Delete(Find(9));printf("length after delete: %d\n",GetLength());Insert(0,-1);PrintList();printf("length:%d\n",GetLength());PrintList();Delete(Find(1));Delete(Find(3));Delete(Find(5));ListIndex();return 0;}int IsEmpty(void ){return  _next[_L] == NIL;}int IsFull(void){return _F == NIL;}int IsLast(int pos){return _next[pos] == NIL;}int AllocateObject(void){int address = NIL;if (!IsFull() ){address = _F;_F = _next[ _F ];_prev[ _F ] = NIL;}return address;}void CreateList(void){int i;_L = 0;_next[ _L ] =NIL;_F = 1;for ( i=_F; i<MAX_ELEMENT; i++ ){_next[ i ] = i+1;_prev[ i ] = i-1;}_prev[ _F ] = NIL;_next[ i ] = NIL;}int GetLength(void){int len = 0;int node = _next[_L];while( node != NIL ){len++;node = _next[node];}return len;}int Insert(ElementType e, int pos){int i = 0;int address_cur;int address_pre;int address_new;if ( -1 == pos ){pos = GetLength();}if ( pos > GetLength() || pos < 0 || IsFull() ){return -1;}address_cur = _next[_L];address_pre = _L;while ( i<pos && address_cur!=NIL ){i++;address_cur = _next[ address_cur ];address_pre = _next[ address_pre ];}address_new = AllocateObject();_key[ address_new ] = e;_next[ address_new ] = address_cur;_prev[ address_new ] = address_pre;_next[ address_pre ] = address_new;if ( address_cur != NIL ){_prev[ address_cur ] = address_new;}return 0;}int Find(ElementType e){int i = 0;int node = _next[ _L ];if ( IsEmpty() ){return -1;}while ( node!=NIL && _key[node]!=e ){node = _next[ node ];i++;}if ( node!=NIL ){return i;}else{return -1;}}void FreeObject(int pos){if ( IsEmpty() ){return;}_next[ pos ] = _F;_prev[ _F ] = pos;_prev[ pos ] = NIL;_F = pos;}int Delete(int pos){int a = _next[ _L ];int i = 0;int len = GetLength();if ( pos<0 || pos>=len ){return -1;}while( i<pos ){a = _next[ a ];i++;}_next[ _prev[a] ] = _next[ a ];if ( _next[ a ] != NIL ){_prev[ _next[a] ] = _prev[ a ];}FreeObject(a);return 0;}void PrintList(void){int i = _next[ _L ];while( i != NIL ){printf("%d,",_key[i]);i = _next[ i ];}printf("\n");}void ListIndex(void){int i;printf("L = %d\n", _L);printf("F = %d\n", _F);printf("      ");for ( i=0; i<=MAX_ELEMENT; i++ ){printf("%5d", i);}printf("\n");printf("_next:  ");for (i=0; i<=MAX_ELEMENT; i++){printf("%3d, ",_next[i]);}printf("\n");printf("_key:   ");for (i=0; i<=MAX_ELEMENT; i++){printf("%3d, ",_key[i]);}printf("\n");printf("_prev:  ");for (i=0; i<=MAX_ELEMENT; i++){printf("%3d, ",_prev[i]);}printf("\n");}