hdu 1251 字典树模板题 ---多串 查找单词出现次数

这道题题目里没有给定数据范围 我开了2005  疯狂的WA

然后开了50000, A掉  我以为自己模板理解错  然后一天没吃饭,饿得胃疼还是想着把这题A掉再去吃,谁知竟然是这样的问题,,,呵呵~~~

只是记录下这道题学到的方法吧:

    for(rt = 0; *s; rt = nxt, ++s)
    {
        nxt=tree[rt][*s-tb];
        if(!nxt)
        {
            nxt=tree[rt][*s-tb]=top;
            memset(tree[top],0,sizeof(tree[top]));
            top++;
        }
        tree[nxt][tk]++;//////////
    }
//////////////处,假设改为tree[rt][tk]表示某个节点有几个孩子,tree[nxt][tk]++经过当前字母的单词个数


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

const int tk=26;
const int tb='a';
const int MAXN= 500000;

int top,tree[MAXN][tk+2];

void init()
{
    top=1;
    memset(tree[0],0,sizeof(tree[0]));
}

void Insert(char *s, int Rank=1)
{
    int rt,nxt;
    for(rt = 0; *s; rt = nxt, ++s)
    {
        nxt=tree[rt][*s-tb];
        if(!nxt)
        {
            nxt=tree[rt][*s-tb]=top;
            memset(tree[top],0,sizeof(tree[top]));
            top++;
        }
        tree[nxt][tk]++;
    }
}

int sea(char *s)
{
    int rt;
    for(rt=0;rt=tree[rt][*s-tb];)
    {
        if(*(++s)==0)return tree[rt][tk];
    }
    return 0;
}

char str[150],pat[150];

int main()
{
   //freopen("hdu1251.txt","r",stdin);
    char cc;
    int ans=0;
    init();
    while(gets(str)&&str[0])
    {
        Insert(str);
    }
    while(~scanf("%s",pat))
    {
        //cout << pat << endl;
        printf("%d
",sea(pat));
    }

    return 0;
}


原文地址:https://www.cnblogs.com/hrhguanli/p/4012902.html