hdu 1251 字典树

#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>using namespace std;const int maxn=27;const int maxm=27;char s[maxm],str[maxn];struct node{    int n;    node *next[maxn];    node()    {        memset(next,0,sizeof(next));        n=1;    }};void Insert(node *rt,char *str){    int i=0;    node *p=rt;    while(str[i])    {        int k=str[i++]-'a';        if(p->next[k]==NULL) p->next[k]=new node();       else p->next[k]->n++;        p=p->next[k];    }}int find(node *rt,char *s){    int i=0,j=0;    node *p=rt;    while(s[i])    {        int k=s[i++]-'a';        if(p->next[k]==NULL) return 0;        p=p->next[k];    }    return p->n;}int main(){    //freopen("//media/学习/ACM/input.txt","r",stdin);    node *rt=new node();    rt->n=0;    while(gets(s)&&strcmp(s,"")!=0)    {        Insert(rt,s);    }    while(scanf("%s",str)!=EOF)    {        int ans=find(rt,str);        cout<<ans<<endl;    }    return 0;}