제출 #377144

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
377144		Gurban	Evacuation plan (IZhO18_plan)	C++17	100 / 100	2458 ms	42748 KiB

plan

/*
ID: gurban1
LANG: C++
TASK: 
*/
#include <bits/stdc++.h>
using namespace std;

using ll = long long;

const int maxn=1e5+5;
int n,m,k,qr,p[maxn];
int dis[maxn],vis[maxn];
int l[maxn],r[maxn],ans[maxn];
vector<int>md[maxn];
vector<pair<int,int>>E[maxn],nd;
priority_queue<pair<int,int>>q;

int ata(int x){
	if(p[x] == x) return x;
	return p[x] = ata(p[x]);
}

void un(int a,int b){
	int x = ata(a),y=ata(b);
	if(x != y) p[y] = x; 
}

int main(){
	// freopen("","r",stdin);
	// freopen("","w",stdout);

	ios::sync_with_stdio(false);
	cin.tie(0);

	cin >> n >> m;
	for(int i = 1;i <= m;i++){
		int x,y,w; cin >> x >> y >> w;
		E[x].push_back({y,w});
		E[y].push_back({x,w});
	}
	for(int i = 1;i <= n;i++) dis[i] = 1e9;
	cin >> k;
	for(int i = 1;i <= k;i++){
		int x; cin >> x;
		dis[x] = 0;
		q.push({0,x});
	}
	while(!q.empty()){
		int x = q.top().second;
		q.pop();
		if(vis[x]) continue;
		vis[x] = 1;
		for(auto i : E[x]){
			if(dis[i.first] > dis[x] + i.second){
				dis[i.first] = dis[x] + i.second;
				q.push({-dis[i.first],i.first});
			}
		}
	}

	for(int i = 1;i <= n;i++) nd.push_back({dis[i],i});
	sort(nd.begin(),nd.end());
	reverse(nd.begin(),nd.end());
	nd.insert(nd.begin(),{0,0});

	cin >> qr;
	vector<pair<int,int>>v(qr+1);
	for(int i = 1;i <= qr;i++){
		cin >> v[i].first >> v[i].second;
		l[i] = 1,r[i] = n;
	}
	// for(int i = 1;i <= n;i++) cout<<nd[i].first<<' '<<nd[i].second<<'\n';
	for(int tt = 0;tt <= 22;tt++){
		for(int i = 1;i <= n;i++) md[i].clear(),p[i] = i,vis[i]=0;
		for(int i = 1;i <= qr;i++){
			if(l[i] > r[i]) continue;
			md[(l[i]+r[i])/2].push_back(i);
		}
		for(int i = 1;i <= n;i++){
			vis[nd[i].second] = 1;
			for(auto j : E[nd[i].second]) if(vis[j.first]) un(nd[i].second,j.first);
			for(auto j : md[i]){
				if(ata(v[j].first) == ata(v[j].second)){
					ans[j] = nd[i].first;
					r[j] = i - 1;
				}
				else l[j] = i + 1;
			}
		}
	}
	for(int i = 1;i <= qr;i++) cout<<ans[i]<<'\n';
}
/*
9 12
1 9 4
1 2 5
2 3 7
2 4 3
4 3 6
3 6 4
8 7 10
6 7 5
5 8 1
9 5 7
5 4 12
6 8 2
2
4 7
5
1 6
5 3
4 8
5 8
1 5


9 12
1 9 4
1 2 5
2 3 7
2 4 3
4 3 6
3 6 4
8 7 10
6 7 5
5 8 1
9 5 7
5 4 12
6 8 2
2
4 7
1
5 3
*/

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 46 / 46