제출 #887909

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
887909		pcc	Evacuation plan (IZhO18_plan)	C++14	100 / 100	312 ms	37824 KiB

plan

#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 inf = 1e9+10;
const int mxn = 1e5+10;
vector<pii> paths[mxn];
int dist[mxn];
vector<pii> req[mxn],v;
int dsu[mxn],sz[mxn];
bitset<mxn> active;
int ans[mxn*5];
priority_queue<pii,vector<pii>,greater<pii>> pq;
int n,m;

void DIJKSTRA(){
	while(!pq.empty()){
		auto now = pq.top();
		pq.pop();
		if(now.fs != dist[now.sc])continue;
		for(auto nxt:paths[now.sc]){
			if(dist[nxt.fs]>dist[now.sc]+nxt.sc){
				dist[nxt.fs] = now.fs+nxt.sc;
				pq.push({dist[nxt.fs],nxt.fs});
			}
		}
	}
	return;
}

int root(int k){
	return k == dsu[k]?k:dsu[k] = root(dsu[k]);
}
void onion(int a,int b,int c){
	a = root(a),b = root(b);
	if(a == b)return;
	if(req[a].size()<req[b].size()){
		swap(a,b);
	}
	while(!req[b].empty()){
		auto tmp = req[b].back();
		req[b].pop_back();
		if(root(tmp.fs) == a){
			if(ans[tmp.sc] == -1)ans[tmp.sc] = c;
		}
		else req[a].push_back(tmp);
	}
	if(sz[a]<sz[b]){
		req[a].swap(req[b]);
		swap(a,b);
	}
	dsu[b] = a;
	sz[a] += sz[b];
	return;
}

int main(){
	ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin>>n>>m;
	for(int i = 0;i<m;i++){
		int a,b,c;
		cin>>a>>b>>c;
		paths[a].push_back({b,c});
		paths[b].push_back({a,c});
	}
	fill(dist,dist+n+1,inf);
	int k;
	cin>>k;
	while(k--){
		int tmp;
		cin>>tmp;
		pq.push({0,tmp});
		dist[tmp] = 0;
	}
	DIJKSTRA();
	for(int i =1;i<=n;i++)v.push_back({dist[i],i});
	sort(v.rbegin(),v.rend());

	for(int i = 1;i<=n;i++)dsu[i] = i,sz[i] = 1;
	int q;
	cin>>q;
	fill(ans,ans+q+1,-1);
	for(int i = 1;i<=q;i++){
		int a,b;
		cin>>a>>b;
		req[a].push_back({b,i});
		req[b].push_back({a,i});
	}
	for(auto &i:v){
		active[i.sc] = true;
		for(auto nxt:paths[i.sc]){
			if(active[nxt.fs])onion(nxt.fs,i.sc,i.fs);
		}
	}
	for(int i = 1;i<=q;i++)cout<<ans[i]<<'\n';
	return 0;
}

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