[动态树 LCT] BZOJ 2594 [Wc2006]水管局长数据加强版

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<map>
#include<algorithm>
using namespace std;
typedef pair<int,int> abcd;

inline char nc()
{
static char buf[100000],*p1=buf,*p2=buf;
if (p1==p2) { p2=(p1=buf)+fread(buf,1,100000,stdin); if (p1==p2) return EOF; }
return *p1++;
}

inline void read(int &x)
{
char c=nc(),b=1;
for (;!(c>='0' && c<='9');c=nc()) if (c=='-') b=-1;
for (x=0;c>='0' && c<='9';x=x*10+c-'0',c=nc()); x*=b;
}

int n,m;

int u[1000005],v[1000005],w[1000005],ivst[1000005];

struct Splay{
struct node{
int size,idx,rev;
int val,maximum;
node *p,*ch[2],*fat,*mpos;
inline void setc(node *c,int d) { ch[d]=c; c->p=this; }
inline bool dir() { return p->ch[1]==this; }
inline void update() {
size=ch[0]->size+ch[1]->size+1;
maximum=val; mpos=this;
if (ch[0]->maximum>maximum)
maximum=ch[0]->maximum,mpos=ch[0]->mpos;
if (ch[1]->maximum>maximum)
maximum=ch[1]->maximum,mpos=ch[1]->mpos;
}
inline void reverse() { rev^=1; swap(ch[0],ch[1]); }
inline void pushdown(node *null){
if (rev){
if (ch[0]!=null) ch[0]->reverse();
if (ch[1]!=null) ch[1]->reverse();
rev=0;
}
}
}*null,Mem[1200005];
Splay() { null=Mem; null->p=null->ch[0]=null->ch[1]=null->fat=null; null->size=0; null->maximum=-(1<<30)-(1<<29); null->mpos=null; }
inline void rot(node *x){
if (x==null || x->p==null) return ;
bool d=x->dir(); node *p=x->p;
if (p->p!=null) p->p->setc(x,p->dir()); else x->p=null;
p->setc(x->ch[d^1],d); x->setc(p,d^1); p->update(); x->update(); swap(x->fat,p->fat);
}
node *sta[1200005];
inline void splay(node *x){
int pnt=0; node *y=x;
while (y!=null) sta[++pnt]=y,y=y->p;
for (int i=pnt;i;i--) sta[i]->pushdown(null);
while (x->p!=null)
if (x->p->p==null)
rot(x);
else
x->dir()==x->p->dir()?(rot(x->p),rot(x)):(rot(x),rot(x));
}
inline node *Access(node *x){
node *y=null;
while (x!=null)
{
splay(x);
x->ch[1]->p=null; x->ch[1]->fat=x;
x->setc(y,1); y->fat=null;
x->update();
y=x; x=x->fat;
}
return y;
}
inline void Link(node *x,node *y){
if (Jud(x,y)) return;
Access(x)->reverse();
splay(x);
x->fat=y;
Access(x);
}
inline void Cut(node *x){
Access(x);
splay(x);
x->ch[0]->p=null; x->ch[0]=null;
x->fat=null; x->update();
}
inline void Cut(node *x,node *y){
Access(x)->reverse();
Cut(y);
}
inline node *Root(node *x){
Access(x);
splay(x);
node *y=x;
while (y->ch[0]!=null) y->pushdown(null),y=y->ch[0];
return y;
}
inline bool Jud(node *x,node *y){
return Root(x)==Root(y);
}
inline int Query(node *x,node *y){
Access(x)->reverse();
return Access(y)->maximum;
}
inline node *Road(node *x,node *y){
Access(x)->reverse();
return Access(y)->mpos;
}
}LCT;

Splay::node *pos[1200005];

inline void Init(){
for (int i=1;i<=n+m;i++){
pos[i]=LCT.Mem+i;
pos[i]->p=pos[i]->ch[0]=pos[i]->ch[1]=pos[i]->fat=LCT.null;
pos[i]->val=-1<<30; pos[i]->maximum=-1<<30; pos[i]->mpos=pos[i];
pos[i]->idx=i; pos[i]->size=1;
}
}

struct event{
int f,u,v;
int idx;
bool operator < (const event &B) const{
return w[idx]<w[B.idx];
}
}eve[1200005];
int tot,icnt,pnt;

int ans[100005];
map<abcd,int> Map;

int fat[100005];
inline int getfat(int u){
return u==fat[u]?u:fat[u]=getfat(fat[u]);
}

inline void Kru()
{
int fx,fy,itot=0;
for (int i=1;i<=n;i++) fat[i]=i;
for (int i=1;i<=m;i++)
if (!ivst[i])
eve[++tot].f=2,eve[tot].u=u[i],eve[tot].v=v[i],eve[tot].idx=i;
sort(eve+pnt+1,eve+tot+1);
for (int i=pnt+1;i<=tot;i++)
{
fx=getfat(eve[i].u); fy=getfat(eve[i].v);
if (fx!=fy)
{
fat[fx]=fy;
LCT.Link(pos[eve[i].u],pos[eve[i].idx+n]);
LCT.Link(pos[eve[i].v],pos[eve[i].idx+n]);
itot++;
if (itot==n-1) break;
}
}
}

int main()
{
int iu,iv,Q;
freopen("t.in","r",stdin);
freopen("t.out","w",stdout);
read(n); read(m); read(Q);
Init();
for (int i=1;i<=m;i++)
{
read(u[i]),read(v[i]),read(w[i]);
pos[i+n]->val=w[i]; pos[i+n]->update();
if (u[i]>v[i]) swap(u[i],v[i]);
Map.insert(make_pair(abcd(u[i],v[i]),i));
}
for (int i=1;i<=Q;i++)
{
read(eve[++tot].f); read(eve[tot].u); read(eve[tot].v);
if (eve[tot].u>eve[tot].v) swap(eve[tot].u,eve[tot].v);
if (eve[tot].f==2)
ivst[eve[tot].idx=Map[abcd(eve[tot].u,eve[tot].v)]]=1;
else if (eve[tot].f==1)
eve[tot].idx=++icnt;
}
pnt=tot;
Kru();
for (int i=pnt;i;i--)
if (eve[i].f==1)
{
ans[eve[i].idx]=LCT.Query(pos[eve[i].u],pos[eve[i].v]);
}
else
{
iu=eve[i].u; iv=eve[i].v;
Splay::node *road=LCT.Road(pos[iu],pos[iv]);
if (road->val>w[eve[i].idx])
{
LCT.Cut(road,pos[u[road->idx-n]]);
LCT.Cut(road,pos[v[road->idx-n]]);
LCT.Link(pos[n+eve[i].idx],pos[iu]);
LCT.Link(pos[n+eve[i].idx],pos[iv]);
}
}
for (int i=1;i<=icnt;i++)
printf("%d\n",ans[i]);
return 0;
}