hdu--1251--字典树

赤裸裸的字典树...就来熟悉下字典树的 顺便注意下写的时候的各种小细节

　　　　　　touch  me

#include <iostream>
#include <cstring>
using namespace std;

const int size = 26;
char str[size];
typedef struct trie
{
    trie* next[size];
    int cnt;
};
trie* root;

void init()
{
    root = new trie;
    for( int i = 0 ; i<size ; i++ )
        root->next[i] = NULL;
}

void create( char* str )
{
    int len = strlen(str);
    trie* p = root;
    //trie* q;
    for( int i = 0 ; i<len ; i++ )
    {
        int id = str[i] - 'a';
        if( p->next[id] == NULL )
        {
            //q = new trie;
            p->next[id] = new trie;
            p->next[id]->cnt = 1;
            for( int j = 0 ; j<size ; j++ )
            {
                p->next[id]->next[j] = NULL;
            }
            //p->next[id] = q;
        }
        else
        {
            p->next[id]->cnt ++;
        }
        p = p->next[id];
    }
}

int find( char* str )
{
    int len = strlen(str);
    trie* p = root;
    for( int i = 0 ; i<len ; i++ )
    {
        int id = str[i] - 'a';
        p = p->next[id];
        if( p==NULL )
        {
            return 0;
        }
    }
    return p->cnt;
}

int main()
{
    init();
    while( gets(str) && str[0]!='' )
    {
        create( str );
    }
    while( cin >> str )
    {
        cout << find(str) << endl;
    }
    return 0;
}

注释的也是正确的... 当时写着来 验证自己想法的=-=

today:

　　if you can't fly then run

　　if you can't run then walk

　　if you can't walk then crawl

　　but wharever you do you have to keep moving forward