题意：求一些指定串的最长公共后缀，动态加入。
傻逼题，被题意坑了，以为要求最长公共LCS。
hash入门题，二分长度以后判断一下是否所有串都相同。
trie+LCA也可以，不过麻烦一点。
trie+LCA：
#include<cstdio>
#include<algorithm>
#include<cstring>
#define fo(i,a,b) for(int i=a;i<=b;i++)
#define fd(i,a,b) for(int i=a;i>=b;i--)
using namespace std;
const int N=1e5+5;
const int M=1e6+5;
int ch[M][27],pos[N],dep[M],fa[M][21];
int val[N],n,m,sz,a[N];
char s[M];
inline void ins(int num)
{
int len=strlen(s+1),x=1;
fd(i,len,1)
{
int c=s[i]-'a';
if (!ch[x][c])
{
ch[x][c]=++sz;
dep[sz]=dep[x]+1,fa[sz][0]=x;
fo(j,1,20)fa[sz][j]=fa[fa[sz][j-1]][j-1];
}
x=ch[x][c];
}
pos[num]=x;
}
inline int lca(int x,int y)
{
if(dep[x]>dep[y])swap(x,y);
int j=20;
while (dep[x]<dep[y])
{
while (j&&dep[fa[y][j]]<dep[x])j--;
y=fa[y][j];
}
j=20;
while(x!=y)
{
while (j&&fa[x][j]==fa[y][j])j--;
x=fa[x][j],y=fa[y][j];
}
return x;
}
int main()
{
freopen("biology.in","r",stdin);
freopen("biology.out","w",stdout);
scanf("%d%d",&n,&m);
sz=1;
fo(i,1,n)
{
scanf("%s",s+1);
ins(i);
}
fo(i,1,m)
{
int op;
scanf("%d",&op);
if (op==1)
{
scanf("%s",s+1);
ins(++n);
}
else
{
int num,k;
scanf("%d",&num);
fo(j,1,num)
{
int x;
scanf("%d",&x);
if (j==1)k=pos[x];
else k=lca(k,pos[x]);
}
printf("%d\n",dep[k]);
}
}
}hash(更快更短空间更少):
#include<cstdio>
#include<algorithm>
#include<cstring>
#define fo(i,a,b) for(int i=a;i<=b;i++)
#define fd(i,a,b) for(int i=a;i>=b;i--)
using namespace std;
const int mo=1e9+7;
int n,m;
const int N=1e6+5;
int hash2[N],now,a[15],p[N],q[N];
typedef unsigned long long ull;
ull hash1[N];
char s[N];
inline void ins(int i)
{
scanf("%s",s);
int len=strlen(s);
p[i]=now+1,q[i]=now+len;
fo(j,1,len)
{
now++;
int tmp=s[len-j]-'a'+1;
if (j==1)hash1[now]=hash2[now]=tmp;
else
{
hash1[now]=hash1[now-1]*27+tmp;
hash2[now]=(1ll*hash2[now-1]*27%mo+tmp)%mo;
}
}
}
inline bool pd(int n,int mid)
{
int w2=hash2[p[a[1]]+mid-1];
ull w1=hash1[p[a[1]]+mid-1];
fo(i,2,n)
if(hash1[p[a[i]]+mid-1]!=w1||hash2[p[a[i]]+mid-1]!=w2)return 0;
return 1;
}
inline int solve(int n)
{
int l=1,r=now,ans=0;
fo(i,1,n)r=min(r,q[a[i]]-p[a[i]]+1);
while (l<=r)
{
int mid=(l+r)>>1;
if (pd(n,mid))l=mid+1,ans=mid;
else r=mid-1;
}
return ans;
}
int main()
{
freopen("biology.in","r",stdin);
freopen("biology.out","w",stdout);
scanf("%d%d",&n,&m);
fo(i,1,n)ins(i);
while (m--)
{
int op;
scanf("%d",&op);
if (op==1)ins(++n);
else
{
int num;
scanf("%d",&num);
fo(i,1,num)scanf("%d",&a[i]);
printf("%d\n",solve(num));
}
}
}