【BZOJ3879】—SvT（后缀自动机+虚树/后缀自动机+单调栈）
后缀数组终于跑过了了
后缀自动机上虚树是显然的
后缀数组就按排序后考虑每个位置的贡献，显然就是左右都比他大的时候
单调栈维护一下就是了
后缀数组+单调栈
#include<bits/stdc++.h>
using namespace std;
const int RLEN=1<<20|1;
inline char gc(){
static char ibuf[RLEN],*ib,*ob;
(ib==ob)&&(ob=(ib=ibuf)+fread(ibuf,1,RLEN,stdin));
return (ib==ob)?EOF:*ib++;
}
inline int read(){
char ch=gc();
int res=0,f=1;
while(!isdigit(ch))f^=ch=='-',ch=gc();
while(isdigit(ch))res=(res+(res<<2)<<1)+(ch^48),ch=gc();
return f?res:-res;
}
inline void readstring(char *s){
int len=0;char c;
while(isspace(c=gc()));
while(s[len++]=c,!isspace(c=gc())&&c!=EOF);
}
#define pii pair<int,int>
#define fi first
#define se second
#define re register
#define pb push_back
#define ll long long
inline void file(){
#ifdef Stargazer
freopen("lx.cpp","r",stdin);
#endif
}
const int N=1000005;
namespace Sa{
int rk[N],sa[N],sa2[N],cnt[N],n,m,s[N],ht[N];
inline void Sort(){
for(int i=1;i<=m;i++)cnt[i]=0;
for(int i=1;i<=n;i++)cnt[rk[sa2[i]]]++;
for(int i=1;i<=m;i++)cnt[i]+=cnt[i-1];
for(int i=n;i>=1;i--)sa[cnt[rk[sa2[i]]]--]=sa2[i];
}
inline void build(){
m=30;
for(int i=1;i<=n;i++)rk[i]=s[i],sa2[i]=i;
Sort();
for(int i=1,pos=0;i<=n&&pos<n;i<<=1){
pos=0;
for(int j=n-i+1;j<=n;j++)sa2[++pos]=j;
for(int j=1;j<=n;j++)if(sa[j]>i)sa2[++pos]=sa[j]-i;
Sort();
pos=1,swap(sa2,rk);
rk[sa[1]]=1;
for(int j=2;j<=n;j++)
rk[sa[j]]=(sa2[sa[j]]==sa2[sa[j-1]])&&(sa2[sa[j]+i]==sa2[sa[j-1]+i])?pos:++pos;
m=pos;
}
for(int i=1,j,k=0;i<=n;ht[rk[i++]]=k)
for(k?k--:0,j=sa[rk[i]-1];s[i+k]==s[j+k];k++);
}
int st[21][N],lg[N];
inline void buildst(){
lg[0]=-1;
for(int i=1;i<=n;i++)lg[i]=lg[i>>1]+1,st[0][i]=ht[i];
for(int i=1;(1<<i)<=n;i++)
for(int j=1;j+(1<<i)-1<=n;j++)
st[i][j]=min(st[i-1][j],st[i-1][j+(1<<(i-1))]);
}
inline int lcp(int x,int y){
x=rk[x],y=rk[y];
if(x>y)swap(x,y);x++;
int t=lg[y-x+1];
return min(st[t][x],st[t][y-(1<<t)+1]);
}
}
inline bool comp(int a,int b){
return Sa::rk[a]<Sa::rk[b];
}
inline void calc(){
static int a[N],val[N],stk[N],l[N],r[N],top;
int n=read(),res=0;
for(int i=1;i<=n;i++)a[i]=read();
sort(a+1,a+n+1,comp),n=unique(a+1,a+n+1)-a-1;
for(int i=1;i<n;i++)val[i]=Sa::lcp(a[i],a[i+1]);
for(int i=1;i<n;i++){
while(top&&val[stk[top]]>=val[i])r[stk[top--]]=i;
stk[++top]=i;
}
while(top)r[stk[top--]]=n;
for(int i=n-1;i;i--){
while(top&&val[stk[top]]>val[i])l[stk[top--]]=i;
stk[++top]=i;
}
while(top)l[stk[top--]]=0;
for(int i=1;i<n;i++)
res+=1ll*val[i]*(i-l[i])*(r[i]-i);
cout<<res<<'\n';
}
int n,m;
char s[N];
int main(){
file();
n=read(),m=read();
readstring(s+1);
Sa::n=strlen(s+1);
for(int i=1;i<=Sa::n;i++)Sa::s[i]=s[i]-'a'+1;
Sa::build(),Sa::buildst();
for(int i=1;i<=m;i++)
calc();
}
后缀自动机+虚树
#include<bits/stdc++.h>
using namespace std;
const int RLEN=1<<20|1;
inline char gc(){
static char ibuf[RLEN],*ib,*ob;
(ib==ob)&&(ob=(ib=ibuf)+fread(ibuf,1,RLEN,stdin));
return (ib==ob)?EOF:*ib++;
}
inline int read(){
char ch=gc();
int res=0,f=1;
while(!isdigit(ch))f^=ch=='-',ch=gc();
while(isdigit(ch))res=(res+(res<<2)<<1)+(ch^48),ch=gc();
return f?res:-res;
}
inline void readstring(char *s){
int len=0;char c;
while(isspace(c=gc()));
while(s[len++]=c,!isspace(c=gc())&&c!=EOF);
}
#define pii pair<int,int>
#define fi first
#define se second
#define re register
#define pb push_back
#define ll long long
inline void file(){
#ifdef Stargazer
freopen("lx.cpp","r",stdin);
#endif
}
const int N=1000005;
namespace Sam{
int nxt[N][26],fa[N],len[N],tot,last;
inline void insert(int c){
int cur=++tot,p=last;last=cur;
len[cur]=len[p]+1;
for(;p&&!nxt[p][c];p=fa[p])nxt[p][c]=cur;
if(!p)fa[cur]=1;
else {
int q=nxt[p][c];
if(len[p]+1==len[q])fa[cur]=q;
else{
int clo=++tot;
memcpy(nxt[clo],nxt[q],sizeof(nxt[q]));
fa[clo]=fa[q],len[clo]=len[p]+1;
fa[q]=fa[cur]=clo;
for(;p&&nxt[p][c]==q;p=fa[p])nxt[p][c]=clo;
}
}
}
}
namespace G{
vector<int> e[N];
int tot,in[N],out[N],dep[N],top[N],fa[N],siz[N],son[N],pos[N];
int a[N],vis[N],ok[N],stk[N],tp,T;
ll ans;
inline void addedge(int u,int v){
e[u].pb(v);
}
inline bool comp(int a,int b){
return in[a]<in[b];
}
void dfs1(int u){
siz[u]=1;
for(int &v:e[u]){
if(v==fa[u])continue;
fa[v]=u,dep[v]=dep[u]+1;
dfs1(v),siz[u]+=siz[v];
if(siz[v]>siz[son[u]])son[u]=v;
siz[v]=0;
}
}
void dfs2(int u,int tp){
in[u]=++tot,top[u]=tp;
if(son[u])dfs2(son[u],tp);
for(int &v:e[u]){
if(v==son[u]||v==fa[u])continue;
dfs2(v,v);
}
out[u]=tot;
e[u].clear();
}
inline int Lca(int u,int v){
while(top[u]!=top[v]){
if(dep[top[u]]<dep[top[v]])swap(u,v);
u=fa[top[u]];
}
return dep[u]<dep[v]?u:v;
}
void calc(int u){
siz[u]=ok[u],ok[u]=0;
for(int &v:e[u]){
calc(v);
ans+=1ll*siz[u]*siz[v]*Sam::len[u];
siz[u]+=siz[v];
}
e[u].clear();
}
inline void solve(){
int m=read(),n=0;T++;ans=0;
memset(siz,0,sizeof(siz));
for(int i=1;i<=m;i++){
int p=read();
if(vis[p]==T)continue;
vis[p]=T,a[++n]=pos[p],ok[pos[p]]=1;
}
sort(a+1,a+n+1,comp);
stk[tp=1]=1;
for(int i=1;i<=n;i++){
int lca=Lca(stk[tp],a[i]);
while(in[lca]<in[stk[tp]]){
if(in[lca]>=in[stk[tp-1]]){
addedge(lca,stk[tp--]);
if(stk[tp]!=lca)stk[++tp]=lca;
break;
}
addedge(stk[tp-1],stk[tp]),tp--;
}
stk[++tp]=a[i];
}
while(tp>1)addedge(stk[tp-1],stk[tp]),tp--;
calc(1);cout<<ans<<'\n';
}
}
int n,m;
char s[N];
int main(){
file();
n=read(),m=read();
readstring(s+1);
Sam::last=Sam::tot=1;
for(int i=strlen(s+1);i;i--)Sam::insert(s[i]-'a'),G::pos[i]=Sam::last;
for(int i=2;i<=Sam::tot;i++)G::addedge(Sam::fa[i],i);
G::dfs1(1),G::dfs2(1,1);
for(int i=1;i<=m;i++)
G::solve();
}
