hdu 1251(字典树)

/*
*  字典树 
*/
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>

using namespace std;

const int N = 11;

char str[N];
struct node {//节点数据 
    int c;  //统计前缀个数 
    node *child[26];
    node() {//初始化 
        c = 1;
        for (int i=0; i<26; ++i) child[i] = NULL;
    }
}*root;

void insert(char str[]) {
    node *p = root;
    for (int k,i=0; str[i]; ++i, p=p->child[k]) {
        k = str[i] - 'a';
        if (p->child[k]) ++p->child[k]->c;
        else p->child[k] = new node();
    }
}

int search(char str[]) {
    node *p = root;
    for (int k,i=0; str[i]; ++i) {
        k = str[i] - 'a';
        if (p->child[k]) p = p->child[k];
        else return 0;
    }
    return p->c;
}

int main() {
    root = new node();
    while (gets(str), strcmp(str, "")) insert(str);
    while (scanf("%s", str) != EOF) printf ("%d\n", search(str));
    return 0;
}