[SCOI2012]喵星球上的点名[广义后缀自动机]

题目链接
这道题一看就是SAM傻逼题吧
建一个广义后缀自动机,直接大力跑就可以了。
第二问的话可以存储每个节点可以作为哪些单词的结尾就可以了
luogu最后一个点TLE,我也不知道怎么回事

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cctype>
#include<map>
#include<vector>
using namespace std;
inline void read(int &x)
{
    int s=0,w=1;
    char c=getchar();
    while(!isdigit(c)){if(c=='-')w=-1;c=getchar();}
    while(isdigit(c)){s=(s<<3)+(s<<1)+c-'0',c=getchar();}
    x=s*w;
}
inline void write(int x)
{
    if(x<0)putchar('-'),x=-x;
    if(x>9)write(x/10);
    putchar(x%10+'0');
}
const int MAXN=400010;
int len[MAXN],fa[MAXN],tot=1,last=1,id[MAXN],a[MAXN>>2],sum[MAXN],cnt[MAXN];
map<int,int>trans[MAXN];
vector<int>mark[MAXN];
inline void extend(int c,int k)
{
    int v=last,u=++tot;
    last=u,len[u]=len[v]+1;
    while(v&&!trans[v][c])trans[v][c]=u,v=fa[v];
    if(!v)fa[u]=1;
    else
    {
        int x=trans[v][c];
        if(len[x]==len[v]+1)fa[u]=x;
        else
        {
            int y=++tot;
            trans[y]=trans[x],mark[y]=mark[x];
            fa[y]=fa[x],fa[x]=fa[u]=y,len[y]=len[v]+1,id[y]=id[x],cnt[y]=cnt[x];
            while(v&&trans[v][c]==x)trans[v][c]=y,v=fa[v];
        }
    }
    for(;u;u=fa[u])
    {
        if(id[u]^k)id[u]=k,cnt[u]++,mark[u].push_back(k);
        else break;
    }
}
inline int solve(int l)
{
    register int i,now=1;
    for(i=1;i<=l;i++)
    {
        if(trans[now][a[i]])
        now=trans[now][a[i]];
        else break;
    }
    if(i!=l+1)return 0;
    for(vector<int>::iterator it=mark[now].begin();it!=mark[now].end();++it)sum[*it]++;
    return cnt[now];
}
int n,m;
int main()
{
    read(n),read(m);
    for(register int i=1,l;i<=n;i++)
    {
        read(l),last=1;
        for(register int j=1;j<=l;j++)read(a[j]),extend(a[j],i);
        read(l),last=1;
        for(register int j=1;j<=l;j++)read(a[j]),extend(a[j],i);
    }
    while(m--)
    {
        int l;
        read(l);
        for(register int i=1;i<=l;i++)read(a[i]);
        write(solve(l)),putchar(10);
    }
    for(register int i=1;i<=n;i++)write(sum[i]),putchar(' ');
    putchar(10);
}

2018.6.7update
TLE的原因是第二问统计答案的方式太暴力,复杂度会达到 O ( n m )
被学长调教♂一番,据说这种做法复杂度期望 n n
先贴上代码

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<map>
using namespace std;
const int MAXN=300010;
int fa[MAXN<<1],len[MAXN<<1],tot=1,last=1,las[MAXN<<1],cnt[MAXN<<1],mark[MAXN<<1],ans[MAXN];
map<int,int>trans[MAXN];
inline void extend(int c,int id)
{
    int v=last,u=++tot;
    len[u]=len[v]+1,last=u;
    while(v&&!trans[v][c])trans[v][c]=u,v=fa[v];
    if(!v)fa[u]=1;
    else
    {
        int x=trans[v][c];
        if(len[x]==len[v]+1)fa[u]=x;
        else
        {
            int y=++tot;
            trans[y]=trans[x];
            fa[y]=fa[x],fa[u]=fa[x]=y,len[y]=len[v]+1,las[y]=las[x],cnt[y]=cnt[x];
            while(v&&trans[v][c]==x)trans[v][c]=y,v=fa[v];
        }
    }
    while(u&&(las[u]^id))las[u]=id,++cnt[u],u=fa[u];
}
inline void modify(int x,int y){while(x&&(las[x]^y))las[x]=y,ans[y]+=mark[x],x=fa[x];}
inline int match(int *str,int l)
{
    register int i,now=1;
    for(i=1;i<=l;i++)
    {
        if(trans[now][str[i]])now=trans[now][str[i]];
        else break;
    }
    if(i==l+1){++mark[now];return cnt[now];}
    else return 0;
}
const int N=50010;
int n,m,p,a[MAXN],leng[N][2],b[MAXN];
int main()
{
    scanf("%d%d",&n,&m);
    for(register int i=1;i<=n;i++)
    {
        scanf("%d",&leng[i][0]),last=1;
        for(register int j=1;j<=leng[i][0];j++)scanf("%d",&a[++p]),extend(a[p],i);
        scanf("%d",&leng[i][1]),last=1;
        for(register int j=1;j<=leng[i][1];j++)scanf("%d",&a[++p]),extend(a[p],i);
    }
    while(m--)
    {
        int l;
        scanf("%d",&l);
        for(register int i=1;i<=l;i++)scanf("%d",&b[i]);
        printf("%d\n",match(b,l));
    }
    p=0;
    register int now=1;
    memset(las,0,sizeof(las));
    for(register int i=1;i<=n;i++)
    {
        now=1;
        for(register int j=1;j<=leng[i][0];j++)
        modify(now=trans[now][a[++p]],i);
        now=1;
        for(register int j=1;j<=leng[i][1];j++)
        modify(now=trans[now][a[++p]],i);
        printf("%d ",ans[i]);
    }
    printf("\n");
}

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转载自blog.csdn.net/assass_cannotin/article/details/80564390