Luogu4022 CTSC2012熟悉的文章（广义后缀自动机+二分答案+动态规划+单调队列）

　　对作文库中的串建出广义SAM，然后显然可以二分答案，二分之后考虑暴力dp，设f[i]为前i位最长匹配长度，显然有f[i]=max(f[i-1],f[j]+i-j) (i-j>=l&&j+1~i能在作文库中匹配)。在SAM上跑并记录匹配长度，单调队列优化dp即可。

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define N 2200010
char getc(){char c=getchar();while ((c<'A'||c>'Z')&&(c<'a'||c>'z')&&(c<'0'||c>'9')) c=getchar();return c;}
int gcd(int n,int m){return m==0?n:gcd(m,n%m);}
int read()
{
	int x=0,f=1;char c=getchar();
	while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();}
	while (c>='0'&&c<='9') x=(x<<1)+(x<<3)+(c^48),c=getchar();
	return x*f;
}
int n,m,son[N][2],fail[N],len[N],f[N],q[N],cnt=1,last;
char s[N];
int ins(int c,int p)
{
    if (son[p][c])
    {
        int q=son[p][c];
        if (len[p]+1==len[q]) return q;
        else
        {
            int y=++cnt;
            len[y]=len[p]+1;
            memcpy(son[y],son[q],sizeof(son[q]));
            fail[y]=fail[q],fail[q]=y;
            while (son[p][c]==q) son[p][c]=y,p=fail[p];
            return y;
        }
    }
    else
    {
        int x=++cnt;len[x]=len[p]+1;
        while (!son[p][c]&&p) son[p][c]=x,p=fail[p];
        if (!p) fail[x]=1;
        else
        {
            int q=son[p][c];
            if (len[p]+1==len[q]) fail[x]=q;
            else
            {
                int y=++cnt;
                len[y]=len[p]+1;
                memcpy(son[y],son[q],sizeof(son[q]));
                fail[y]=fail[q],fail[x]=fail[q]=y;
                while (son[p][c]==q) son[p][c]=y,p=fail[p];
            }
        }
        return x;
    }
}
bool check(int k,int n)
{
	int x=1,l=0;int head=0,tail=0;
	for (int i=1;i<=n;i++)
	{
		while (!son[x][s[i]-'0']&&x) x=fail[x],l=len[x];
		if (!x) x=1,l=0;
		else x=son[x][s[i]-'0'],l++;
		f[i]=f[i-1];
		if (i>=k)
		{
			while (head<=tail&&f[q[tail]]-q[tail]<=f[i-k]-(i-k)) tail--;
			q[++tail]=i-k;
		}
		if (l>=k)
		{
			while (q[head]<i-l) head++;
			f[i]=max(f[i],f[q[head]]-q[head]+i);
		}
	}
	return f[n]*10>=n*9;
}
int main()
{
#ifndef ONLINE_JUDGE
	freopen("a.in","r",stdin);
	freopen("a.out","w",stdout);
	const char LL[]="%I64d
";
#else
	const char LL[]="%lld
";
#endif
	n=read(),m=read();
	for (int i=1;i<=m;i++)
	{
		scanf("%s",s+1);int _=strlen(s+1);last=1;
		for (int i=1;i<=_;i++) last=ins(s[i]-'0',last);
	}
	for (int i=1;i<=n;i++)
	{
		scanf("%s",s+1);int _=strlen(s+1);
		int l=1,r=_,ans=0;
		while (l<=r)
		{
			int mid=l+r>>1;
			if (check(mid,_)) ans=mid,l=mid+1;
			else r=mid-1;
		}
		printf("%d
",ans);
	}
	return 0;
}