Hdu 3065 病毒侵袭持续中//Aho-Corasick Automaton

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这道题题目没说是多case，所以无情wa了半个多小时。囧！AC自动机的水题，下面是代码：

#include<stdio.h>#include<string.h>#include<queue>#include<ctype.h>using namespace std;#define maxn 1010*50#define maxc 26int ch[maxn][maxc];int val[maxn];int f[maxn];int cnt;int ans[maxn];char str[2000010];char P[1005][60];void init(){    cnt = 1;    memset(ch[0],0,sizeof(ch[0]));    memset(ans,0,sizeof(ans));}void ac_insert_trie(char *s,int key){    int u = 0;    while(*s)    {        int id = *s - 'A';        if(ch[u][id] == 0)        {            memset(ch[cnt],0,sizeof(ch[cnt]));            val[cnt] = 0;            ch[u][id] = cnt++;        }        u = ch[u][id];        s++;    }    val[u] = key;}void ac_get_fail(){    queue<int> q;    for(int c = 0; c < maxc; c++)    {        int u = ch[0][c];        if(u)        {            f[u] = 0;            q.push(u);        }    }    while(!q.empty())    {        int r = q.front(); q.pop();        for(int c = 0; c < maxc; c++)        {            int u = ch[r][c];            if(u)            {                q.push(u);                int v = f[r];                while(v && !ch[v][c]) v = f[v];                f[u] = ch[v][c];            }        }    }}void ac_find(int len){    int j = 0;    for(int i = 0; i < len; i++)    {        if(!isupper(str[i]))        {            j = 0;            continue;        }        int c = str[i] - 'A';        while(j && !ch[j][c]) j = f[j];        j = ch[j][c];        int t = j;        while(t && val[t])        {            ans[val[t]]++;            t = f[t];        }    }}int main(){    int n;    while(scanf("%d",&n) != EOF){            init();    for(int i = 1; i <= n; i++)    {        scanf("%s",P[i]);        ac_insert_trie(P[i],i);    }    ac_get_fail();    scanf("%s",str);    ac_find(strlen(str));    for(int i = 1; i <= n; i++)    {        if(ans[i])        {            printf("%s: %d\n",P[i],ans[i]);        }    }    }    return 0;}