hdu 1251 统计难题

这是字典树的入门题，很经典，也很容易，代码比较简单易懂，所以我就不解释了。不会字典树的同学请先上网搜索相关知识～～～

/* THE PROGRAM IS MADE BY PYY */
/*----------------------------------------------------------------------------//
	Copyright (c) 2011 panyanyany All rights reserved.

        URL   : http://acm.hdu.edu.cn/showproblem.php?pid=1251
        Name  : 统计难题

        Date  : Thursday, May 5, 2011
        Time Stage : 2 hours around

        Result:
3910551	2011-05-05 01:45:27	Accepted	1251
93MS	43784K	1423 B
C++	pyy


Test Data:

Review:
初级题目，果然一次就AC了……
//----------------------------------------------------------------------------*/
#include <iostream>
#include <conio.h>
#include <stdio.h>
#include <string.h>
using namespace std;
struct node 
{
	int cnt;
	node *childs[26];
	node() { cnt = 0; memset(childs, 0, sizeof(childs)); }
};
node *root = new node;
int i, j, k, index;
node *current, *newnode;

void insert( char * str )
{
	current = root;
	for( i = 0; str[i] != '/0'; ++i )
	{
		index = str[i] - 'a';
		if( current->childs[index] != NULL )
		{
			current = current->childs[index];
			++current->cnt;
		}
		else 
		{
			newnode = new node;
			++newnode->cnt;
			current->childs[index] = newnode;
			current = newnode;
		}
	}
}

int is_find( char *str )
{
	current = root;
	for( i = 0; str[i] != '/0'; ++i )
	{
		index = str[i] - 'a';
		if( current->childs[index] == NULL )
			return 0;
		current = current->childs[index];
	}
	
	return current->cnt;
}
			
int main()
{
	char str[20];
	while( gets(str), strcmp(str, "") )
		insert( str );
	while( gets(str) != NULL )
		printf( "%d/n", is_find(str) );
	return 0;
}