hdu 2896 病毒侵襲 AC自動機

AC自動機模板。學習的是學長的寫法，感覺很好。

#include<stdio.h>
#include<string.h>
#include<queue>
#include<algorithm>

using namespace std;

const int N = 502;
const int MAX = 130;

char virus[205];
char web[10005];
int flag[1005][5];

struct Trie{
    int next[MAX];
    int fail;
    int cnt;
    void init()
    {
        memset(next, -1, sizeof(next));
        fail = -1;
        cnt = 0;
    }
};

Trie trie[100002];
int sz;

void init()
{
    sz = 1;
    trie[0].init();
}

void myinsert(char* s, int tag)
{
    int i = 0;
    int p = 0;
    while(s[i])
    {
        int ch = s[i];
        if(trie[p].next[ch] == -1)
        {
            trie[sz].init();
            trie[p].next[ch] = sz++;
        }
        p = trie[p].next[ch];
        i++;
    }
    trie[p].cnt = tag;
}

void buildACautomachine()
{
    int i, pre, pre_fail, child;
    trie[0].fail = -1;
    queue<int> que;
    que.push(0);
    while(!que.empty())
    {
        pre = que.front();
        que.pop();
        for(i = 0; i < MAX; i++)
        {
            if(trie[pre].next[i] != -1)
            {
                child = trie[pre].next[i];
                pre_fail = trie[pre].fail;
                while(pre_fail != -1)
                {
                    if(trie[pre_fail].next[i] != -1)
                    {
                        trie[child].fail = trie[pre_fail].next[i];
                        break;
                    }
                    pre_fail = trie[pre_fail].fail;
                }
                if(pre_fail == -1)
                    trie[child].fail = 0;
                que.push(child);
            }
        }
    }
}

int query(char* s, int t)
{
    int i = 0, cnt = 0, p = 0, tmp;
    int k = 0;
    while(s[i])
    {
        int ch = s[i];
        while(trie[p].next[ch] == -1 && p != 0)
            p = trie[p].fail;
        p = trie[p].next[ch];
        tmp = p = (p == -1?0:p);
        while(tmp != 0 && trie[tmp].cnt != -1)
        {
            if(trie[tmp].cnt != 0)
                flag[t][k++] = trie[tmp].cnt;
            tmp = trie[tmp].fail;
        }
        i++;
    }
    return k;
}

int main()
{
    int n, m;
    while(~scanf("%d", &n))
    {
        init();
        memset(flag, 0, sizeof(flag));
        for(int i = 0; i < n; i++){
            scanf("%s", virus);
            myinsert(virus, i+1);
        }
        buildACautomachine();
        scanf("%d", &m);
        int tot = 0;
        for(int i = 0; i < m; i++){
            scanf("%s", web);
            int num;
            if(num = query(web, i))
            {
                tot++;
                sort(flag[i], flag[i] + num);
                printf("web %d:", i + 1);
                for(int j = 0; j < num; j++)
                   printf(" %d", flag[i][j]);
                puts("");
            }
        }
        printf("total: %d\n", tot);

    }

    return 0;
}

/*
3
aaa
bbb
ccc
2
aaabbbccc
bbaacc
*/