Submission #240159

#	Time	Username	Problem	Language	Result	Execution time	Memory
240159		MvC	Synchronization (JOI13_synchronization)	C++11	100 / 100	258 ms	21240 KiB

synchronization

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
#define rc(x) return cout<<x<<endl,0
#define pb push_back
#define mkp make_pair
#define in insert
#define er erase
#define fd find
#define fr first
#define sc second
#define all(x) x.begin(),x.end()
#define lun(x) (int)x.size()
typedef long long ll;
typedef long double ld;
const ll INF=0x3f3f3f3f3f3f3f3f;
const ll llinf=(1LL<<60);
const int inf=(1<<30);
const int nmax=1e5+50;
const ll mod=1e9+7;
using namespace std;
int n,m,q,i,t,tin[nmax],tout[nmax],up[nmax][20],rs[nmax],fw[nmax],ex[nmax],ey[nmax],x,y,z,l[nmax];
vector<int>a[nmax];
void dfs(int x,int p)
{
	tin[x]=++t;
	up[x][0]=p;
	for(int i=1;i<17;i++)up[x][i]=up[up[x][i-1]][i-1];
	for(int i=0;i<lun(a[x]);i++)if(a[x][i]!=p)dfs(a[x][i],x);
	tout[x]=t;
}
void upd(int i,int v)
{
	for(;i<=n;i+=i&(-i))fw[i]+=v;
}
int qry(int i)
{
	int ans=0;
	for(;i>=1;i-=i&(-i))ans+=fw[i];
	return ans;
}
int fnd(int x)
{
	int cur=qry(tin[x]);
	for(int i=16;i>=0;i--)if(qry(tin[up[x][i]])==cur)x=up[x][i];
	return x;
}
int main()
{
	//freopen("sol.in","r",stdin);
	//freopen("sol.out","w",stdout);
	//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
	ios_base::sync_with_stdio(false);cin.tie(0);cerr.tie(0);cout.tie(0);
	cin>>n>>m>>q;
	for(i=1;i<n;i++)
	{
		cin>>x>>y;
		ex[i]=x,ey[i]=y;
		a[x].pb(y);
		a[y].pb(x);
	}
	dfs(1,1);
	for(i=1;i<=n;i++)
	{
		upd(tin[i],1);
		upd(tout[i]+1,-1);
		rs[i]=1;
	}
	for(i=1;i<n;i++)if(tin[ex[i]]>tin[ey[i]])swap(ex[i],ey[i]);
	while(m--)
	{
		cin>>i;
		x=ex[i],y=ey[i],z=fnd(x);
		if(l[i]==-1)
		{
			upd(tin[y],1);
			upd(tout[y]+1,-1);
			l[i]=rs[y]=rs[z];
		}
		else
		{
			upd(tin[y],-1);
			upd(tout[y]+1,1);
			rs[z]+=rs[y]-l[i];
			l[i]=-1;
		}
	}
	while(q--)
	{
		cin>>x;
		cout<<rs[fnd(x)]<<'\n';
	}
	return 0;
}

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