哈希表

//哈希做查找
//建立一个哈希表，然后查找元素
#include <iostream>
const int tablelength = 15;
int maxtimes = 4;
int keynum = 13; //小于容量15的最大素数
int invalidedata = -1;//hash表中没有内容时每个单元初始化为-1
int fullflag  = -2; //hash表满
int notfind = -3;
typedef struct node
{
    int data;
    ///////如果还有其他数据的话
};
void init(node mydata[],int length)
{
    for(int i = 0;i<length;i++)
        mydata[i].data = invalidedata;
    return ;
}
int hashalgo(int i)
{
    return i%keynum;
}
int increment()//如果遇到冲突，每次探查位置加1
{
    return 1; 
}
int insert(node table[],int i)
{
    int temp;
    int times = 0;
    
    temp = hashalgo(i);
    //一次就找到
    if(table[temp].data==invalidedata ||table[temp].data == i)
    {
        table[temp].data = i;
        return 1; //正常找到
    }
    else //已经有内容
    {
        while(1)
        {
            temp += increment();
            if(temp>=tablelength)
                return fullflag;
            if(table[temp].data==invalidedata ||table[temp].data == i)
            {
                table[temp].data = i;
                return 1;
            }
        }
    }
}

void inserthashtable(node table[],int data[])
{
    int ret;
    for(int i = 0;i<12;i++)
    {
        ret = insert(table,data[i]);
        if(ret == fullflag)
        {
            printf("hash表已满\n");
            exit(1);
        }
    }
    return ;

}
int search(node mydata[],int i)
{
    int temp;
    int times = 0;
    
    temp = hashalgo(i);
    //一次就找到
    if(mydata[temp].data == i)
        return temp;
    else 
    {
        while(times<maxtimes)
        {
            temp += increment();
            if(temp>=tablelength)
                return notfind;
            if(mydata[temp].data == i)
                return temp;
            times++;
        }
        return notfind;
    }
}
int main()
{
    node mydata[tablelength];
    init(mydata,tablelength);
    int anotherdata[12] = {1,2,4,5,21,15,99,8,0,13,26,27};
    inserthashtable(mydata,anotherdata);
    for(int i = 0;i<tablelength;i++)
        printf("%d ",mydata[i].data);
    int ret = search(mydata,5);
    printf("5的查找结果为：%d\n",ret);
    ret = search(mydata,100);
    printf("100的查找结果为：%d\n",ret);
    ret = search(mydata,27);
    printf("27的查找结果为：%d\n",ret);
 
    return 0;
}