HDU 4787 GRE Revenge

　Now Coach Pang is preparing for the Graduate Record Examinations as George did in 2011. At each day, Coach Pang can:

• "+\(w\)": learn a word \(w\)
• "?\(p\)": read a paragraph \(p\), and count the number of learnt words. Formally speaking, count the number of substrings of \(p\) which is a learnt words.
  　　Given the records of N days, help Coach Pang to find the count. For convenience, the characters occured in the words and paragraphs are only '0' and '1'.

强制在线。

考虑暴力根号筹够，每 \(\sqrt{n}\) 个重建 AC 自动机。

开两个Ac自动机，一个拿来存最近根号个，每次插入重构。另一个每个根号个就插入重构。

#include<bits/stdc++.h>
using namespace std;
const int N=1e5+5,M=5e6+5;
typedef long long LL;
int q[N],l,r,m,t,n,ln[N];
LL ls;
char str[N],ss[M],st[M];
void shift(char ss[])
{
	int m=strlen(ss);
	for(int i=ls%m;i<m;i++)
		st[i-ls%m]=ss[i];
	for(int i=0;i<ls%m;i++)
		st[m-ls%m+i]=ss[i];
	for(int i=0;i<m;i++)
		ss[i]=st[i];
}
struct ACAM{
	int tr[N][2],ch[N][2],idx,c[N],fil[N],tg[N];
	void insert(int l,int r)
	{
		int u=0;
		for(int i=l;i<r;i++)
		{
			if(!ch[u][str[i]-'0'])
				ch[u][str[i]-'0']=++idx;
			u=ch[u][str[i]-'0'];
		}
		tg[u]=1;
	}
	int find(int l,int r)
	{
		int u=0;
		for(int i=l;i<r;i++)
		{
			if(!ch[u][str[i]-'0'])
				return 0;
			u=ch[u][str[i]-'0'];
		}
		return tg[u];
	}
	LL ask()
	{
		int u=0;
		LL ans=0;
		for(int i=0;ss[i];i++)
			u=tr[u][ss[i]-'0'],ans+=c[u];
		return ans;
	}
	void clr()
	{
		for(int i=0;i<=idx;i++)
			ch[i][0]=ch[i][1]=fil[i]=tg[i]=c[i]=tr[i][0]=tr[i][1]=0;
		idx=0;
	}
	void build()
	{
		memset(c,0,sizeof(c));
		l=1,r=0;
		for(int i=0;i<2;i++)
			if(tr[0][i]=ch[0][i])
				q[++r]=ch[0][i];
		while(l<=r)
		{
			for(int i=0;i<2;i++)
			{
				if(ch[q[l]][i])
					fil[q[++r]=tr[q[l]][i]=ch[q[l]][i]]=tr[fil[q[l]]][i];
				else
					tr[q[l]][i]=tr[fil[q[l]]][i];
			}
			++l;
		}
		for(int i=0;i<=idx;i++)
			c[i]=tg[i];
		for(int i=0;i<=idx;i++)
			c[q[i]]+=c[fil[q[i]]];
	}
}x,y;
int main()
{
	scanf("%d",&t);
	for(int T=1;T<=t;T++)
	{
		printf("Case #%d:\n",T);
		x.clr(),y.clr();
		scanf("%d",&n),m=ls=0;
		const int B=2;
		for(int i=1;i<=n;i++)
		{
			char op=getchar();
			while(op^'+'&&op^'?')
				op=getchar();
			if(op=='+')
			{
				++m;
				scanf("%s",str+ln[m-1]);
				shift(str+ln[m-1]);
				ln[m]=ln[m-1]+strlen(str+ln[m-1]);
				if(m%B==0)
				{
					for(int i=m-B+1;i<=m;i++)
					{
						x.insert(ln[i-1],ln[i]);
						x.build();
					}
					y.clr();
				}
				else
				{
					if(!x.find(ln[m-1],ln[m]))
					{
						y.insert(ln[m-1],ln[m]);
						y.build();
					}
				}
			}
			else
			{
				scanf("%s",ss);
				shift(ss);
				printf("%lld\n",ls=x.ask()+y.ask());
			}
		}
	}
}