Submission #960886

#	Time	Username	Problem	Language	Result	Execution time	Memory
960886		pcc	Synchronization (JOI13_synchronization)	C++17	30 / 100	211 ms	68636 KiB

synchronization

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

#define ll long long
#define pll pair<ll,ll>
#define pii pair<int,int>
#define fs first
#define sc second
#define tlll tuple<ll,ll,ll>

const int mxn = 1e5+10;
int bit[mxn];
pii eul[mxn],edges[mxn];
int N,M,Q;
int dep[mxn];
vector<int> tree[mxn];
bitset<mxn> done;
int mv[mxn*2];
int rt;
int par[mxn][20];
int pt = 0;
set<int> st[mxn];

void modify(int p,int v){
	for(;p<mxn;p+=p&-p)bit[p] += v;
	return;
}
int getval(int p){
	int re = 0;
	for(;p>0;p-= p&-p)re += bit[p];
	return re;
}

void dfs(int now){
	eul[now].fs = ++pt;
	for(int i = 1;i<20;i++)par[now][i] = par[par[now][i-1]][i-1];
	for(auto nxt:tree[now]){
		if(nxt == par[now][0])continue;
		par[nxt][0] = now;
		dep[nxt] = dep[now]+1;
		dfs(nxt);
	}
	eul[now].sc = pt;
	return;
}

void change(int p){
	auto [a,b] = edges[p];
	if(dep[a]>dep[b])swap(a,b);
	if(done[p]){
		done[p] = false;
		modify(eul[b].fs,-1);
		modify(eul[b].sc+1,1);
		return;
	}
	done[p] = true;
	modify(eul[b].fs,1);
	modify(eul[b].sc+1,-1);
	int up = b;
	for(int i = 19;i>=0;i--){
		if(getval(eul[b].fs)-getval(eul[par[up][i]].fs) == dep[b]-dep[par[up][i]])up = par[up][i];
	}
	if(up == b)return;
	if(st[up].size()<st[b].size())st[up].swap(st[b]);
	for(auto &i:st[b])st[up].insert(i);
	st[b].clear();
	return;
}

int main(){
	ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin>>N>>M>>Q;
	for(int i = 1;i<N;i++){
		auto &[a,b] = edges[i];
		cin>>a>>b;
		tree[a].push_back(b);
		tree[b].push_back(a);
	}
	for(int i = 1;i<=M;i++)cin>>mv[i];
	while(Q--){
		cin>>rt;
		par[rt][0] = rt;
		dfs(rt);
		done.reset();
		for(int i = 1;i<=N+1;i++)bit[i] = 0;
		for(int i = 1;i<=N;i++)st[i].clear();
		for(int i = 1;i<=N;i++)st[i].insert(i);
		for(int i = 1;i<=M;i++)change(mv[i]);
		cout<<st[rt].size()<<'\n';
	}
	return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 10
• Subtask 4: 0 / 20
• Subtask 5: 0 / 40