hdu2896病毒侵袭(ac自动机）

链接

ac自动机的模板题

说2个注意的地方 一是题目说明包含所有ASCII字符，可以开到0-127 包含空格

题目会输入多个源串，在加完当前的val值时，不应清0，可以开个标记数组。

#include <iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<stdlib.h>
#include<vector>
#include<cmath>
#include<queue>
#include<set>
using namespace std;
#define N 100010
#define M 510
#define LL long long
#define INF 0xfffffff
const double eps = 1e-8;
const double pi = acos(-1.0);
const double inf = ~0u>>2;
const int child_num = 128;
int g;
int o[M];
char s[N];
bool f[M];
class ACAutomo
{
    private:
    int ch[N][child_num];
    int val[N];
    int fail[N];
    int Q[N];
    int id[128];
    int sz;
    public:
    void init()
    {
        fail[0] = 0;
        for(int i = 0; i < child_num ; i++)
        id[i] = i;
    }
    void reset()
    {
        memset(ch[0],0,sizeof(ch[0]));
        sz = 1;
    }
    void insert(char *a,int key)
    {
        int p = 0 ;
        for( ; *a ; a++)
        {
            int d = id[*a];
            if(ch[p][d]==0)
            {
                memset(ch[sz],0,sizeof(ch[sz]));
                val[p] = 0;
                ch[p][d] = sz++;
            }
            p = ch[p][d];
        }
        val[p]=key;
    }
    void construct()
    {
        int i,head=0,tail = 0;
        for(i = 0 ;i < child_num ; i++)
        {
            if(ch[0][i])
            {
                Q[tail++] = ch[0][i];
                fail[ch[0][i]] = 0;
            }
        }
        while(head!=tail)
        {
            int u = Q[head++];
            for(i = 0; i < child_num ; i++)
            {
                if(ch[u][i])
                {
                    Q[tail++] = ch[u][i];
                    fail[ch[u][i]] = ch[fail[u]][i];
                }
                else
                ch[u][i] = ch[fail[u]][i];
            }
        }
    }
    void work(char *s)
    {
        int i,k = strlen(s);
        memset(f,0,sizeof(f));
        int p = 0;
        for(i = 0 ;i < k ; i++)
        {
            int d = id[s[i]];
            p = ch[p][d];
            int tmp = p;
            while(tmp!=0&&(val[tmp]!=0||f[val[tmp]]))
            {
                if(!f[val[tmp]])
                o[g++] = val[tmp];
                f[val[tmp]] = 1;
                tmp = fail[tmp];
            }
        }
    }
}ac;
int main()
{
    int n,m,i;
    char vir[210];
    ac.init();
    while(scanf("%d%*c",&n)!=EOF)
    {
        ac.reset();
        for(i = 1; i <= n; i++)
        {
            gets(vir);
            ac.insert(vir,i);
        }
        scanf("%d%*c",&m);
        int ans = 0;
        ac.construct();
        for(i = 1; i <= m ;i++)
        {
            gets(s); g = 0 ;
            ac.work(s);
            if(g==0) continue;
            printf("web %d:",i);
            sort(o,o+g);
            for(int j = 0 ;j < g ; j++)
            printf(" %d",o[j]);
            puts("");
            ans++;
        }
        printf("total: %d
",ans);
    }
    return 0;
}