[동적 트리] HDOJ 5467 Clarke and hunger games

시간에 따라 트리를 만들고 LCT의 지속성을 차례로 실현...

#include <bits/stdc++.h>
using namespace std;
typedef long long LL;

#define mp(x, y) make_pair(x, y)
const int maxn = 300005;
const int maxm = 300005;
const int INF = 0x3f3f3f3f;
const int mod = 1e9+7;

struct node *null;
struct node
{
	int size, rev;
	LL val, sum;
	node *fa, *ch[2];

	void init()
	{
		rev = val = sum = 0;
		fa = ch[0] = ch[1] = null;
	}

	inline bool d()
	{
		return fa->ch[1] == this;
	}

	inline bool isroot()
	{
		return fa == null || fa->ch[0] != this && fa->ch[1] != this;
	}

	inline void setc(node *p, int d)
	{
		ch[d] = p;
		p->fa = this;
	}

	inline void pushup()
	{
		sum = ch[0]->sum * ch[1]->sum % mod * ((val - 1) * val / 2) % mod;
	}

	inline void flip()
	{
		if(this == null) return;
		swap(ch[0], ch[1]);
		rev ^= 1;
	}
	
	inline void pushdown()
	{
		if(rev) {
			ch[0]->flip();
			ch[1]->flip();
			rev = 0;
		}
	}

	inline void go()
	{
		if(!isroot()) fa->go();
		pushdown();
	}

	void rot()
	{
		node *f = fa, *ff = fa->fa;
		int c = d(), cc = fa->d();
		f->setc(ch[!c], c);
		this->setc(f, !c);
		if(ff->ch[cc] == f) ff->setc(this, cc);
		else this->fa = ff;
		f->pushup();
	}

	node* splay()
	{
		go();
		while(!isroot()) {
			if(!fa->isroot()) d() == fa->d() ? fa->rot() : rot();
			rot();
		}
		pushup();
		return this;
	}

	node* access()
	{
		for(node *p = this, *q = null; p != null; q = p, p = p->fa) {
			p->splay()->setc(q, 1);
			p->pushup();
		}
		return splay();
	}

	inline void makeroot()
	{
		access()->flip();
	}

	node* getroot() {
		node *x;
		for(x = access(); x->pushdown(), x->ch[0] != null; x = x->ch[0]);
		return x;
	}

	void cut()
	{
		access();
		ch[0]->fa = null;
		ch[0] = null;
		pushup();
	}

	void cut(node *o)
	{
		makeroot();
		o->cut();
	}

	void link(node *p)
	{
		makeroot();
		fa = p;
	}
}*Node[maxn], pool[maxm], *tail;

struct ope
{
	int kk, u, v;
	ope(int kk = 0, int u = 0, int v = 0) : kk(kk), u(u), v(v) {}
}op[maxn];

struct Edge
{
	int v;
	Edge *next;
}*H[maxn], *edges, E[maxn];

vector<int> to[maxn];
LL res[maxn];
int T[maxn];
int a[maxn];
int n, m;

void addedges(int u, int v)
{
	edges->v = v;
	edges->next = H[u];
	H[u] = edges++;
}


node* newnode(int val)
{
	tail->init();
	tail->val = val;
	tail->sum = tail->val * (tail->val - 1) / 2;
	return tail++;
}

void init()
{
	tail = pool;
	null = newnode(1);
	null->sum = 1;
	edges = E;
	memset(H, 0, sizeof H);
	memset(T, 0, sizeof T);
	memset(res, -1, sizeof res);
}

bool add(int u, int v)
{
	if(u == v) return 0;
	if(Node[u]->getroot() == Node[v]->getroot()) return 0;
	Node[u]->link(Node[v]);
	return true;
}

bool del(int u, int v)
{
	if(u == v) return 0;
	if(Node[u]->getroot() != Node[v]->getroot()) return 0;
	Node[u]->makeroot();
	Node[v]->access();
	if(Node[v]->ch[0] != Node[u] || Node[u]->ch[1] != null) return 0; 
	else Node[v]->cut(Node[u]);
	return 1;
}

LL query(node *a, node *b)
{
	a->access();
	for(a = null; b != null; a = b, b = b->fa) {
		b->splay();
		if(b->fa == null) return b->ch[1]->sum * a->sum % mod * (b->val * (b->val - 1) / 2) % mod;
		b->setc(a, 1);
		b->pushup();
	}
}

void modify(int u, LL val)
{
	Node[u]->access();
	Node[u]->val = val;
	Node[u]->pushup();
}

void dfs(int ti)
{
	LL tmp = 0;
	int flag = 0;
	
	if(op[ti].kk == 1) flag = add(op[ti].u, op[ti].v);
	
	if(op[ti].kk == 2) flag = del(op[ti].u, op[ti].v);
	
	if(op[ti].kk == 4) {
		if(Node[op[ti].u]->getroot() != Node[op[ti].v]->getroot()) res[ti] = 0;
		else res[ti] = query(Node[op[ti].u], Node[op[ti].v]);
	}
	
	if(op[ti].kk == 5) {
		tmp = a[op[ti].u];
		a[op[ti].u] = op[ti].v;
		modify(op[ti].u, op[ti].v);
	}
	
	for(Edge *e = H[ti]; e; e = e->next) dfs(e->v);
	
	if(op[ti].kk == 2 && flag) add(op[ti].u, op[ti].v);
	
	if(op[ti].kk == 1 && flag) del(op[ti].u, op[ti].v);

	if(op[ti].kk == 5) {
		a[op[ti].u] = tmp;
		modify(op[ti].u, tmp);
	}
}

void work()
{
	scanf("%d%d", &n, &m);
	for(int i = 1; i <= n; i++) to[i].clear();
	for(int i = 1; i <= n; i++) scanf("%d", &a[i]);
	
	for(int i = 1; i <= n; i++) Node[i] = newnode(a[i]);
	
	for(int i = 1; i <= m; i++) {
		int kk, u, v;
		scanf("%d", &kk);
		if(kk == 3) scanf("%d", &u), T[i] = u;
		else scanf("%d%d", &u, &v), T[i] = i-1;
		op[i] = ope(kk, u, v);
	}
	for(int i = 1; i <= m; i++) addedges(T[i], i);
	dfs(0);
	for(int i = 1; i <= m; i++) if(res[i] != -1) printf("%lld
", res[i]);
}

int main()
{
	int _;
	scanf("%d", &_);
	while(_--) {
		init();
		work();
	}
	
	
	return 0;
}