hdu1251统计难题（字典树小试牛刀）

来源：互联网发布：matlab数组写入excel 编辑：程序博客网时间：2024/06/14 03:42

->题目猛戳这里<-

题目大意：略

题目分析：建棵字典树就ok，详情请见代码：

#include <iostream>#include<cstdio>#include<cstring>#include<cstdlib>using namespace std;char s[20];typedef struct node{    struct node *next[26];    int num;}tree;void init(tree *t){t->num = 0;for(int i = 0;i < 26;i ++)t->next[i] = NULL;}void build(tree *t,int id){    if(t->next[s[id] - 'a'] == NULL)    {        t->next[s[id] - 'a'] = (tree *)malloc(sizeof(tree));        init(t->next[s[id] - 'a']);        t->next[s[id] - 'a']->num = 1;    }    else    {        t->next[s[id] - 'a']->num ++;    }    if(s[id + 1] == '\0')        return;    else        build(t->next[s[id] - 'a'],id + 1);}int query(tree * t,int id){    if(t->next[s[id] - 'a'] == NULL)        return 0;    if(s[id + 1] == '\0')        return t->next[s[id] - 'a']->num;    return query(t->next[s[id] - 'a'],id + 1);}int main(){    tree *root = NULL;    root = (struct node *)malloc(sizeof(struct node));    init(root);    while(gets(s))    {        //puts(s);        if(strlen(s) == 0)            break;        build(root,0);    }    while(gets(s) != NULL)    {        int ans;        ans = query(root,0);        printf("%d\n",ans);    }    return 0;}//140MS43896K