HDU 2896 病毒侵袭 [AC自动机]

http://acm.hdu.edu.cn/showproblem.php?pid=2896

题意：给n个模式串m个文本串，问每个文本串里出现了哪些模式串。每个模式串唯一。

ac自动机中，用end数组把模式串的id记录下来就好。

#include<cassert>
#include<algorithm>
#include<cmath>
#include<iostream>
#include<cstdio>
#include<cstring>
#include<vector>
#include<set>
#include<queue>
#include<map>
using namespace std;
#define rep(i,f,t) for(int i = (f), _end = (t); i <= _end; ++i)
#define dep(i,f,t) for(int i = (f), _end = (t); i >= _end; --i)
#define clr(c,x) memset(c,x,sizeof(c));
#define debug(x) cout<<"debug  "<<x<<endl;
const int INF = 0x3f3f3f3f;
typedef long long int64;

inline int RD(){ int res; scanf("%d",&res); return res; }

#define Rush for(int casn = RD(), cas = 1; cas <= casn; ++cas)

//*******************************************************************************

const int maxn = 501;
struct Trie{
    int next[maxn*200][128];
    int fail[maxn*200];
    int end[maxn*200];
    int sz;
    void init(){
        sz = 0;
        clr(next[0],0);
    }
    int newnode(){
        ++sz;
        clr(next[sz],0);
        fail[sz] = end[sz] = 0;
        return sz;
    }
    void insert(char *s, int id){
        int u = 0;
        while(*s){
            int &v = next[u][*s];
            if(!v) v = newnode();
            u = v;
            ++s;
        }
        end[u] = id;
    }
    void build(){
        queue<int> Q;
        rep(i,1,127){
            if(next[0][i])Q.push(next[0][i]);
        }
        while(!Q.empty()){
            int u = Q.front();
            Q.pop();
            int fu = fail[u];
            rep(c,1,127){
                int &v = next[u][c];
                if(v){
                    Q.push(v);
                    fail[v] = next[fu][c];
                }else{
                    v = next[fu][c];
                }
            }
        }
    }
    void query(char *s, vector<int> &res){
        int u = 0;
        while(*s){
            u = next[u][*s];
            int k = u;
            while(k){
                if(end[k]){
                    res.push_back(end[k]);
                }
                k = fail[k];
            }
            ++s;
        }
        sort(res.begin(),res.end());
    }
}ac;

char str[10005];
int main(){
    int n,m;
    while(~scanf("%d",&n)){
        ac.init();
        rep(i,1,n){
            scanf("%s",str);
            ac.insert(str,i);
        }
        ac.build();
        scanf("%d",&m);
        vector<int> res;
        int tot = 0;
        rep(i,1,m){
            scanf("%s",str);
            res.clear();
            ac.query(str,res);
            if(!res.empty()){
                ++tot;
                printf("web %d:",i);
                rep(j,0,res.size()-1){
                    printf(" %d",res[j]);
                }
                printf("
");
            }
        }
        printf("total: %d
",tot);
    }
    return 0;
}

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