Submission #552152

#	Time	Username	Problem	Language	Result	Execution time	Memory
552152		errorgorn	Jail (JOI22_jail)	C++17	60 / 100	2495 ms	1048576 KiB

jail

// Super Idol的笑容
//    都没你的甜
//  八月正午的阳光
//    都没你耀眼
//  热爱105°C的你
// 滴滴清纯的蒸馏水

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;

#define int long long
#define ll long long
#define ii pair<ll,ll>
#define iii pair<ii,ll>
#define fi first
#define se second
#define endl '\n'
#define debug(x) cout << #x << ": " << x << endl

#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define lb lower_bound
#define ub upper_bound

#define rep(x,start,end) for(auto x=(start)-((start)>(end));x!=(end)-((start)>(end));((start)<(end)?x++:x--))
#define all(x) (x).begin(),(x).end()
#define sz(x) (int)(x).size()

#define indexed_set tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>
//change less to less_equal for non distinct pbds, but erase will bug

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

int n,q;
vector<int> al[120005];

int d[120005];
int tkd[120005][19];
ii idx[120005][19];
vector<int> al2[5000005];
int IDX;

void dfs(int i,int p){
	for (auto it:al[i]){
		if (it==p) continue;
		
		d[it]=d[i]+1;
		int curr=tkd[it][0]=i;
		
		idx[it][0]={IDX,IDX+1};
		al2[IDX++].clear();
		al2[IDX++].clear();
		
		rep(x,0,19){
			if (tkd[curr][x]==-1) continue;
			curr=tkd[it][x+1]=tkd[curr][x];
			
			// idx[it][x+1].fi=IDX;
			// al2[IDX].clear();
			// al2[idx[it][x].fi].pub(IDX);
			// al2[idx[curr][x].fi].pub(IDX);
			// IDX++;
// 			
			// idx[it][x+1].se=IDX;
			// al2[IDX].clear();
			// al2[IDX].pub(idx[it][x].se);
			// al2[IDX].pub(idx[curr][x].se);
			// IDX++;
		}
		
		dfs(it,i);
	}
}

int mov(int i,int k){
	rep(x,0,19) if (k&(1<<x)) i=tkd[i][x];
	return i;
}

int lca(int i,int j){
	if (d[i]<d[j]) swap(i,j);
	i=mov(i,d[i]-d[j]);
	if (i==j) return i;
	
	rep(x,19,0) if (tkd[i][x]!=tkd[j][x]){
		i=tkd[i][x];
		j=tkd[j][x];
	}
	
	return tkd[i][0];
}

int dist(int i,int j){
	int g=lca(i,j);
	return d[i]+d[j]-2*d[g];
}

int vis[5000005];
bool cyc;
void dfs2(int i){
	vis[i]=1;
	
	for (auto it:al2[i]){
		if (vis[it]==1) cyc=true;
		if (vis[it]==0) dfs2(it);
	}
	
	vis[i]=2;
}

signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin.exceptions(ios::badbit | ios::failbit);
	
	int TC;
	cin>>TC;
	while (TC--){
		cin>>n;
		
		rep(x,1,n+1) al[x].clear();
		
		int a,b;
		rep(x,1,n){
			cin>>a>>b;
			al[a].pub(b);
			al[b].pub(a);
		}
		cin>>q;
		
		rep(x,0,q) al2[x].clear();
		IDX=q;
		
		idx[1][0]={IDX,IDX+1};
		al2[IDX++].clear();
		al2[IDX++].clear();
		
		rep(x,1,n+1) rep(y,0,19) tkd[x][y]=-1;
		dfs(1,-1);
		
		//rep(x,1,n+1) cout<<idx[x][0].fi<<" "<<idx[x][0].se<<endl;
		
		rep(i,0,q){
			cin>>a>>b;
			al2[i].pub(idx[a][0].fi);
			al2[i].pub(idx[a][0].se);
			al2[idx[b][0].fi].pub(i);
			al2[idx[b][0].se].pub(i);
			
			int g=lca(a,b);
			
			if (a!=g){
				int curr=tkd[a][0];
				while (curr!=g){
					al2[i].pub(idx[curr][0].fi);
					al2[idx[curr][0].se].pub(i);
					curr=tkd[curr][0];
				}
			}
			if (b!=g){
				int curr=tkd[b][0];
				while (curr!=g){
					al2[i].pub(idx[curr][0].fi);
					al2[idx[curr][0].se].pub(i);
					curr=tkd[curr][0];
				}
			}
			
			if (g!=a && g!=b){
				al2[i].pub(idx[g][0].fi);
				al2[idx[g][0].se].pub(i);
			}
		}
		
		// rep(x,0,IDX){
			// for (auto y:al2[x]) cout<<x<<" "<<y<<endl;
		// }
		
		cyc=false;
		rep(x,0,IDX) vis[x]=0;
		rep(x,0,IDX) if (vis[x]==0) dfs2(x);
		
		if (!cyc) cout<<"Yes"<<endl;
		else cout<<"No"<<endl;
	}
}

• Subtask 1: 0 / 5
• Subtask 2: 5 / 5
• Subtask 3: 16 / 16
• Subtask 4: 28 / 28
• Subtask 5: 0 / 12
• Subtask 6: 11 / 11
• Subtask 7: 0 / 23