貪心算法
#include <stdio.h>
#include<malloc.h>
#include<string.h>
#define HASH_LEN 50
#define M 47
#define NAME_NO 30
typedef struct NAME
{
char *py; //名字的拼音
int k; //拼音所對應的整數
}NAME;
NAME NameList[HASH_LEN];
typedef struct hterm //哈希表
{
char *py; //名字的拼音
int k; //拼音所對應的整數
int si; //查找長度
}HASH;
HASH HashList[HASH_LEN];
void InitNameList()
{
NameList[0].py="liujianwen";
NameList[1].py="shiyongqing";
NameList[2].py="zhongjialiang";
NameList[3].py="fenfyubao";
NameList[4].py="nonghuajian";
NameList[5].py="liaojianxin";
NameList[6].py="lianjinsong";
NameList[7].py="liuxiao";
NameList[8].py="lushaojian";
NameList[9].py="liangshiqian";
NameList[10].py="lichao";
NameList[11].py="liwei";
NameList[12].py="luojiayu";
NameList[13].py="lvjun";
NameList[14].py="liuhongxiu";
NameList[15].py="huangkeqiang";
NameList[16].py="weiyihui";
NameList[17].py="liaohaoqiang";
NameList[18].py="zhangdeshang";
NameList[19].py="zhouzihe";
NameList[20].py="chenqiuyan";
NameList[21].py="wangliecheng";
NameList[22].py="liaowei";
NameList[23].py="gongxinhua";
NameList[24].py="xiongbei";
NameList[25].py="moshaoxi";
NameList[26].py="lixiaolan";
NameList[27].py="wangjunxiu";
NameList[28].py="qinjinfeng";
NameList[29].py="zhoutong";
char *f;
int r,s0;
for (int i=0;i<NAME_NO;i++)// 求出各個姓名的拼音所對應的整數
{
s0=0;
f=NameList[i].py;
for (r=0;*(f+r) != '\0';r++) //方法：將字符串的各個字符所對應的ASCII碼相加，所得的整數做為哈希表的關鍵字
s0=*(f+r)+s0;
NameList[i].k=s0;
}
}
void CreateHashList()
{
for ( int i=0; i<HASH_LEN;i++)//哈希表的初始化
{
HashList[i].py="";
HashList[i].k=0;
HashList[i].si=0;
}
for ( i=0; i<NAME_NO;)
{
int sum=0;
int adr=(NameList[i].k) % M; //哈希函數
int d=adr;
if(HashList[adr].si==0) //如果不沖突
{
HashList[adr].k=NameList[i].k;
HashList[adr].py=NameList[i].py;
HashList[adr].si=1;
}
else //沖突
{
do
{
d=(d+((NameList[i].k))%10+1)%M; //偽散列
sum=sum+1; //查找次數加1
}while (HashList[d].k!=0);
HashList[d].k=NameList[i].k;
HashList[d].py=NameList[i].py;
HashList[d].si=sum+1;
}i++;
}
}
void FindList()
{
printf("\n\n請輸入姓名的拼音: "); //輸入姓名
char name[20]={0};
scanf("%s",name);
int s0=0;
for (int r=0;r<20;r++) //求出姓名的拼音所對應的整數(關鍵字)
s0+=name[r];
int sum=1;
int adr=s0 % M; //使用哈希函數
int d=adr;
if(HashList[adr].k==s0) //分3種情況進行判斷
printf("\n姓名:%s 關鍵字:%d 查找長度為: 1",HashList[d].py,s0); else if (HashList[adr].k==0)
printf("無該記錄!");
else
{
int g=0;
do
{
d=(d+s0%10+1)%M; //偽散列
sum=sum+1;
if (HashList[d].k==0)
{
printf("無記錄! ");
g=1;
}
if (HashList[d].k==s0)
{
printf("\n姓名:%s 關鍵字:%d 查找長度為:%d",HashList[d].py,s0,sum); g=1;
}
}while(g==0);
}
}
void Display()
{
printf("\n\n地址\t關鍵字\t\t搜索長度\tH(key)\t\t拼音 \n"); //顯示的格式
for(int i=0; i<15; i++)
{
printf("%d ",i);
printf("\t%d ",HashList[i].k);
printf("\t\t%d ",HashList[i].si);
printf("\t\t%d ",(HashList[i].k)%M);
printf("\t %s ",HashList[i].py);
printf("\n");
}
for( i=15; i<30; i++)
{
printf("%d ",i);
printf("\t%d ",HashList[i].k);
printf("\t\t%d ",HashList[i].si);
printf("\t\t%d ",(HashList[i].k)%M);
printf("\t %s ",HashList[i].py);
printf("\n");
}
for( i=30; i<40; i++)
{
printf("%d ",i);
printf("\t%d ",HashList[i].k);
printf("\t\t%d ",HashList[i].si);
printf("\t\t%d ",(HashList[i].k)%M);
printf("\t %s ",HashList[i].py);
printf("\n");
}
for(i=40; i<50; i++)
{
printf("%d ",i);
printf("\t%d ",HashList[i].k);
printf("\t\t%d ",HashList[i].si);
printf("\t\t%d ",(HashList[i].k)%M);
printf("\t %s ",HashList[i].py);
printf("\n");
}
float average=0;
for (i=0;i<HASH_LEN;i++)
average+=HashList[i].si;
average/=NAME_NO;
printf("\n\n平均查找長度：ASL(%d)=%f \n\n",NAME_NO,average); }
int main()
{
printf("\n------------------------哈希表的建立和查找----------------------"); InitNameList();
CreateHashList ();
while(1)
{
printf("\n\n");
printf(" 1. 顯示哈希表\n");
printf(" 2. 查找\n");
printf(" 3. 退出\n");
err:
char ch1;
scanf("%c",&ch1);
if (ch1=='1')
Display();
else if (ch1=='2')
FindList();
else if (ch1=='3')
return 0;
else
{
printf("\n請輸入正確的選擇!");
goto err;
}
}
}