hash

hash  是个好东西啊。 用链表实现，数组实现，  把一

#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
#define MAXD 100003
char word[MAXD][12];
char dict[MAXD][12];
int head[MAXD] = {0};
int next[MAXD];
char t[15];
int hash(char w[]){
    int L = strlen(w);
    int sum = 0;
    for(int i = 0;i < L;i++)
        sum =  10 * sum + w[i];
    return   sum  % MAXD;
}
int add(int n){
    int  x = hash(dict[n]);
    next[n] = head[x];
    head[x] = n;
    return 1;
}
int search_word(){
    int  x = hash(t);
    int  u = head[x];
    while(u){
        if(strcmp(dict[u],t)==0) return u;
        u = next[u];
    }
    return -1;
}
int main(){
    int N = 1;
    char str[30];
    while (gets(str)){
        if(str[0]=='\0')
            break;
        int i;
        for(i = 0; str[i] != ' '; ++i)
            word[N][i] = str[i];
        word[N][i] = '\0';
        char *p = str + i + 1;
        i = 0;
        while (*p)
            dict[N][i++] = *p++;
        dict[N][i] = '\0';
        add(N);
        ++N;
    }
    while (gets(t)) {
        int index = search_word();
        if (index == -1)
            puts("eh");
        else
            printf("%s\n", word[index]);
    }
    return 0;
}

个字符串保存起来， 再查速度很快