LightOJ 1427(AC自动机

题目:给出若干模板串和一个母串,求每个模板串在母串中出现的次数.

思路:AC自动机+后缀链接(last数组)

/*
* @author:  Cwind
*/
///#pragma comment(linker, "/STACK:102400000,102400000")
#include <iostream>
#include <map>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <vector>
#include <queue>
#include <stack>
#include <functional>
#include <set>
#include <cmath>
using namespace std;
#define IOS std::ios::sync_with_stdio (false);std::cin.tie(0)
#define pb push_back
#define PB pop_back
#define bk back()
#define fs first
#define se second
#define sq(x) (x)*(x)
#define eps (3e-7)
#define IINF (1<<29)
#define LINF (1ll<<59)
#define INF (1000000000)
#define FINF (1e3)
#define clr(x) memset((x),0,sizeof (x));
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<int,int> P;

const int maxv=1e5+3000;
const int csize=26;
int ch[maxv*4][csize];
int sz;
bool term[maxv*4];
vector<int> termlist[maxv*4];
void Tclear(){
    sz=1;
    clr(ch[0]);clr(term);
}
int last[maxv*4];
void insert(char *s,int id){
    int u=0,n=strlen(s);
    for(int i=0;i<n;i++){
        int c=s[i]-'a';
        if(!ch[u][c]){
            memset(ch[sz],0,sizeof ch[sz]);
            termlist[sz].clear();
            term[sz]=0;
            ch[u][c]=sz++;
        }
        u=ch[u][c];
    }
    term[u]=1;
    termlist[u].pb(id);
}
int f[maxv*4];
queue<int> Q;
void getFail(){
    f[0]=0;
    for(int c=0;c<csize;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<csize;c++){
            int u=ch[r][c];
            if(!u) continue;
            Q.push(u);
            int v=f[r];
            while(v&&!ch[v][c]){
                v=f[v];
            }
            f[u]=ch[v][c];
            last[u]=term[f[u]]?f[u]:last[f[u]];
        }
    }
}

const int maxlen=1e6+3000;
const int maxn=600;
int T,n;
char r[maxlen];
char M[maxlen];
int ans[maxn];
int cas=0;
int main(){
    freopen("/home/slyfc/CppFiles/in","r",stdin);
    //freopen("defense.in","r",stdin);
    //freopen("defense.out","w",stdout);
    cin>>T;
    while(T--){
        cin>>n;
        printf("Case %d:\n",++cas);
        clr(ans);clr(last);
        Tclear();
        scanf("%s",M);
        for(int i=0;i<n;i++){
            scanf("%s",r);
            insert(r,i+1);
        }
        getFail();
        int len=strlen(M);
        int v=0;
        for(int i=0;i<len;i++){
            int c=M[i]-'a';
            while(v&&!ch[v][c]) v=f[v];
            v=ch[v][c];
            int vv=v;
            while(vv!=0){
                for(int j=0;j<termlist[vv].size();j++){
                    ans[termlist[vv][j]]++;
                }
                vv=last[vv];
            }
        }
        for(int i=1;i<=n;i++)
            printf("%d\n",ans[i]);
    }
    return 0;
}
View Code

 

posted @ 2015-10-13 23:24  PlusSeven  阅读(228)  评论(0编辑  收藏  举报