散列表的C语言实现-开放定址法

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头文件：

#ifndef __HASHTABLE_H#define __HASHTABLE_H/*********************（平方）开放定址散列法***************///如果有冲突发生，那么就尝试另外的单元，直到找到空的单元为止typedef unsigned int index;typedef index position;typedef int ElementType;#define MINTABLESIZE 5struct hashTable;typedef struct HashTable *hashTable;hashTable initializeTable(int tableSize);void destoryTable(hashTable H);position find(ElementType key,hashTable H);void insert(ElementType key,hashTable H);ElementType retrieve(position p,hashTable H);hashTable reHash(hashTable H);int Delete(ElementType key,hashTable H);int nextPrime(int tableSize);int isPrime(int x);int Hash(ElementType key,int tableSize);enum kindOfEntry{legitimate,empty,deleted};struct hashEntry{ElementType element;enum kindOfEntry info;};typedef struct hashEntry cell;struct HashTable{int tableSize;cell *theCells;};

#endif

实现文件：

#include "HashTable.h"#include <stdio.h>#include <stdlib.h>/***********************开发定址法（平方）***********************************/hashTable initializeTable(int tableSize){hashTable table;int i;if(tableSize<MINTABLESIZE){printf("table size is too small\n");exit(-1);}table=(hashTable)malloc(sizeof(struct HashTable));if(!table){printf("out of space\n");exit(-1);}table->tableSize=nextPrime(tableSize);table->theCells=(cell*)malloc(sizeof(cell)*table->tableSize);if(!table->theCells){printf("out of space\n");exit(-1);}for(i=0;i<table->tableSize;i++)table->theCells[i].info=empty;return table;}void destoryTable(hashTable H){free(H->theCells);H=NULL;}position find(ElementType key,hashTable H){position currentPos;int collisionNum;collisionNum=0;currentPos=Hash(key,H->tableSize);while(H->theCells[currentPos].info!=empty&&H->theCells[currentPos].element!=key){//平方探测法currentPos+=2*collisionNum-1;if(currentPos>=H->tableSize)currentPos-=H->tableSize;}return currentPos;}int Delete(ElementType key,hashTable H){position pos;pos=find(key,H);if(H->theCells[pos].info==empty)return 0;else{H->theCells[pos].info=deleted;return 1;}}void insert(ElementType key,hashTable H){position pos;pos=find(key,H);if(H->theCells[pos].info!=legitimate){H->theCells[pos].info=legitimate;H->theCells[pos].element=key;}}ElementType retrieve(position p,hashTable H){}hashTable reHash(hashTable H)//再散列{int i,oldSize;cell *oldCells;oldCells=H->theCells;oldSize=H->tableSize;H=initializeTable(2*oldSize);for(i=0;i<oldSize;i++){if(oldCells[i].info==legitimate)insert(oldCells[i].element,H);}free(oldCells);return H;}int nextPrime(int tableSize){while(1){if(isPrime(tableSize))return tableSize;elsetableSize++;}}int isPrime(int x){int i;for(i=2;i*i<=x;i++){if(x%i==0)return 0;}return 1;}int Hash(ElementType key,int tableSize){return key%tableSize;}/**************************************************************************/

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