# [BZOJ3514] Codechef MARCH14 GERALD07加强版 (CHEF AND GRAPH QUERIES)

## 题意

$$N$$ 个点 $$M$$ 条边的无向图，$$K$$ 次询问保留图中编号在 $$[l,r]$$ 的边的时候图中的联通块个数。

$$1\le N,M,K\le200,000$$

## 题解

### 参考代码

#include <bits/stdc++.h>
#define _O0 __attribute__((optimize("O0")))

const int MAXN=200010;

struct LCT{
#define lch chd[0]
#define rch chd[1]
#define kch chd[k]
#define xch chd[k^1]
struct Node{
int val;
bool rev;
Node* prt;
Node* min;
Node* chd[2];
Node(int val):val(val),rev(false),prt(NULL),min(this),chd{NULL,NULL}{}
inline bool isRoot(){
return this->prt==NULL||(this->prt->lch!=this&&this->prt->rch!=this);
}
inline _O0 void Flip(){
if(this!=NULL){
std::swap(this->lch,this->rch);
this->rev=!this->rev;
}
}
inline void PushDown(){
if(this->rev){
this->lch->Flip();
this->rch->Flip();
this->rev=false;
}
}
inline void Maintain(){
this->min=this;
if(this->lch&&this->lch->min->val<this->min->val)
this->min=this->lch->min;
if(this->rch&&this->rch->min->val<this->min->val)
this->min=this->rch->min;
}
};
std::vector<Node*> N;
LCT(int n):N(n+1){
for(int i=1;i<=n;i++)
N[i]=new Node(INT_MAX);
}
void Rotate(Node* root,int k){
Node* tmp=root->xch;
root->PushDown();
tmp->PushDown();
tmp->prt=root->prt;
if(!root->isRoot()){
if(root->prt->lch==root)
root->prt->lch=tmp;
else
root->prt->rch=tmp;
}
root->xch=tmp->kch;
if(root->xch)
root->xch->prt=root;
tmp->kch=root;
root->prt=tmp;
root->Maintain();
tmp->Maintain();
}

void Splay(Node* root){
while(!root->isRoot()){
int k=root->prt->lch==root;
if(root->prt->isRoot())
Rotate(root->prt,k);
else{
int d=root->prt->prt->lch==root->prt;
Rotate(k==d?root->prt->prt:root->prt,k);
Rotate(root->prt,d);
}
}
}

void Expose(Node* root){
Splay(root);
root->PushDown();
if(root->rch){
root->rch=NULL;
root->Maintain();
}
}

void Access(Node* root){
Expose(root);
Splay(root);
while(root->prt){
Splay(root->prt);
root->prt->PushDown();
root->prt->rch=root;
root->prt->Maintain();
Splay(root);
}
}

void Evert(Node* root){
Access(root);
root->Flip();
}

Node* FindRoot(Node* root){
Access(root);
Node* ans=root;
ans->PushDown();
while(ans->lch){
ans->PushDown();
ans=ans->lch;
}
Splay(ans);
return ans;
}

Evert(b);
b->prt=a;
}

void Cut(Node* a,Node* b){
Evert(a);
Access(b);
b->PushDown();
b->lch->prt=NULL;
b->lch=NULL;
b->Maintain();
}

if(a==b)
return val;
int ret=0;
if(FindRoot(N[a])==FindRoot(N[b])){
Evert(N[a]);
Access(N[b]);
Node* min=N[b]->min;
ret=N[b]->min->val;
Splay(min);
min->lch->prt=NULL;
min->rch->prt=NULL;
}
N.push_back(new Node(val));
return ret;
}
#undef lch
#undef rch
#undef kch
#undef xch
};

struct SegTree{
struct Node{
int l;
int r;
int sum;
Node* lch;
Node* rch;
Node(int l,int r):l(l),r(r),sum(0),lch(NULL),rch(NULL){
if(l!=r){
int mid=(l+r)>>1;
this->lch=new Node(l,mid);
this->rch=new Node(mid+1,r);
}
}
Node(Node* ptr){
*this=*ptr;
}
void Insert(int x){
++this->sum;
if(l!=r){
if(x<=this->lch->r)
(this->lch=new Node(this->lch))->Insert(x);
else
(this->rch=new Node(this->rch))->Insert(x);
}
}
};
std::vector<Node*> N;
SegTree(int n){
N.push_back(new Node(0,n));
}
void Insert(int x){
N.push_back(new Node(*N.rbegin()));
(*N.rbegin())->Insert(x);
}
int Query(int l,int r,int x){
return Query(N[l-1],N[r],x);
}
int Query(Node* aux,Node* root,int x){
if(0<=root->l&&root->r<=x)
return root->sum-aux->sum;
else{
int ans=0;
if(0<=root->lch->r)
ans+=Query(aux->lch,root->lch,x);
if(root->rch->l<=x)
ans+=Query(aux->rch,root->rch,x);
return ans;
}
}
};

int n,m,q,opt;
int lastans;
int ntr[MAXN];

int main(){
scanf("%d%d%d%d",&n,&m,&q,&opt);
LCT* lct=new LCT(n);
SegTree* T=new SegTree(m);
for(int i=1;i<=m;i++){
int a,b;
scanf("%d%d",&a,&b);
}
for(int i=1;i<=m;i++)
T->Insert(ntr[i]);
for(int i=0;i<q;i++){
int l,r;
scanf("%d%d",&l,&r);
l^=opt*lastans;
r^=opt*lastans;
printf("%d\n",lastans=n-T->Query(l,r,l-1));
}
return 0;
}



posted @ 2019-02-13 19:28  rvalue  阅读(182)  评论(0编辑  收藏  举报