HDU-1251统计难题 ,字典树

#include <iostream>
#include <cstring>
#include <algorithm>
#include <string>
#include <cstdio>
using namespace std;

const int maxn = 500000;
struct node {
    node * s[26];
    int num;
};

node a[maxn],*rt;
int p = 0;
char str[11];

node * newNode()
{
    memset(a[p].s,0,sizeof(a[p].s));
    a[p].num = 0;
    return &a[p++];
}

void insert(char * str)
{
    node * cur = rt;
    cur->num++;
    while( *str != ‘\0‘)
    {
        int t = *(str++) - ‘a‘;
        if(cur->s[t]==0)
            cur-> s[t]=newNode();
        cur = cur->s[t];
        cur -> num++;
    }
}

int getans(char *str)
{
    node *cur = rt;
    while(*str!=‘\0‘)
    {
        int t = *(str++) - ‘a‘;
        if(cur->s[t]==0)return 0;
        cur  = cur -> s[t]; 
    }
    return cur->num;
}

int main(){        
    rt = newNode();
    gets(str);
    while(str[0]!=‘\0‘)
    {
        insert(str);
        gets(str);
    }
    while(~scanf("%s",str))
    {
        printf("%d\n",getans(str));
    }
    return 0;
}