哈希查找

记录个demo吧。

建立hash表和search一定要用同一的hash算法。

#include <stdio.h>#include <stdlib.h>#define Max 6#define HashMax 5int data[Max] = {12, 160, 219, 522, 725, 9997};int HashTable[HashMax] = {0};int counter = 1;struct LinkList{int key;struct LinkList *next;};typedef struct LinkList Node;typedef Node *Link;Node HashTable_linklist[HashMax] = {0};static int hash_mod(int key){return key%HashMax;}static int collision_offset(int addr){int offset = 3;return (addr + offset)%HashMax;}static int create_hash_linklist(int key){Link pointer;Link new_node;int index;new_node = (Link) malloc(sizeof(Node));new_node->key = key;new_node->next = NULL;index = hash_mod(key);pointer = HashTable_linklist[index].next;if (pointer != NULL){new_node->next = pointer;HashTable_linklist[index].next = new_node;}elseHashTable_linklist[index].next = new_node;return 0;}int hash_search_linklist(int key){Link pointer;int index;counter = 0;index = hash_mod(key);pointer = HashTable_linklist[index].next;printf("Data[%d]: ", index);while(pointer != NULL){counter++;printf("[%d]", pointer->key);if (pointer->key == key)return 1;elsepointer = pointer->next;}return 0;}static int create_hash(int key){int hash_time = 0;int collision_time = 0;int address = hash_mod(key);int i;while (hash_time < HashMax){if (HashTable[address] == 0) /*尚未被占用*/{HashTable[address] = key;printf("Key : %d => Address %d\n", key, address);for(i = 0; i < HashMax; i++){printf("[%d]", HashTable[i]);}printf("\n");return 1;}else{collision_time++;printf("Collision %d => Address %d\n", collision_time, address);address = collision_offset(address);}hash_time++;}return 0;}/*建立hash Table 必须和Search用同样的方式*/static int hash_search(int key){int address;counter = 0;address = hash_mod(key);while(counter < HashMax){counter++;if (HashTable[address] == key)return 1;elseaddress = collision_offset(address);}return 0;}int main(int argc, char **argv){int key = 522;int index = 0;int i = 0;while(index < Max){if (create_hash(data[index]))printf("Hash Success\n");elseprintf("Hash Fulled\n");index++;}printf("Hash Table : \n");for (i = 0; i < HashMax; i++){printf("[%d]", HashTable[i]);}printf("\n");if (hash_search(key))printf("Search Time = %d\n", counter);elseprintf("Didnot find %d\n", key);counter = 0;index = 0;while(index < Max){if (create_hash_linklist(data[index]))printf("Hash Success\n");elseprintf("Hash Fulled\n");index++;}Link pointer;printf("Linklist Hash Table : \n");for (i = 0; i < HashMax; i++){printf("Table %d: ", i);pointer = HashTable_linklist[i].next;while(pointer != NULL){if (pointer->key > 0)printf("[%d]", pointer->key);pointer = pointer->next;}printf("\n");}printf("\n");printf("goint to search linklist\n");if (hash_search_linklist(key))printf("\nLinkList Search Time = %d\n", counter);elseprintf("Didnot find %d\n", key);}