hdu 1251 统计难题 字典树

在hdu上要用c++提交，要不然会超内存。

传送门：http://acm.hdu.edu.cn/showproblem.php?pid=1251

#include <stdio.h>#include <stdlib.h>#include <string.h>#define maxn 30struct Trie{    Trie * next[maxn];    int v;};Trie * root;void Init_Trie(){    root = (Trie *)malloc(sizeof(Trie));    for(int i=0;i<maxn;i++){        root -> next[i] = NULL;    }}void Add_Trie(char * str){    Trie * p = root , * q;    for(int i=0;str[i]!='\0';i++){        int id = str[i] - 'a';        if(p->next[id]==NULL){            q = (Trie *)malloc(sizeof(Trie));            q -> v = 1;            for(int j=0;j<maxn;j++){                q -> next[j] = NULL;            }            p -> next[id] = q;            p = p -> next[id];        }        else {            p -> next[id]->v++;            p = p -> next[id];        }    }    //p -> v ++;}int Search_Trie(char * str){    Trie * p = root;    for(int i=0;str[i]!='\0';i++){        int id = str[i] - 'a';        p = p -> next[id];        if(p==NULL){            return 0;        }    }    return p -> v;}void Del_Trie(Trie * p){    for(int i=0;i<maxn;i++){        if(p->next[i])Del_Trie(p->next[i]);    }    free(p);}void input(){    char a[15];    Init_Trie();    while(gets(a),a[0]!='\0'){        Add_Trie(a);    }    while(~scanf("%s",a)){        printf("%d\n",Search_Trie(a));    }    Del_Trie(root);}void File(){    freopen("a.in","r",stdin);    freopen("a.out","w",stdout);}int main(void){    //File();    input();    return 0;}