Submission #556293

#	Time	Username	Problem	Language	Result	Execution time	Memory
556293		Hanksburger	Evacuation plan (IZhO18_plan)	C++17	100 / 100	618 ms	57144 KiB

plan

#include <bits/stdc++.h>
using namespace std;
int dist[100005], par[100005], ans[100005];
vector<pair<int, int> > adj[100005];
priority_queue<pair<int, int> > pq;
vector<pair<int, int> > edge;
set<int> s[100005];
bool cmp(pair<int, int> x, pair<int, int> y)
{
	return (min(dist[x.first], dist[x.second])>min(dist[y.first], dist[y.second]));
}
int findPar(int u)
{
	if (par[u]==u)
		return u;
	par[u]=findPar(par[u]);
	return par[u];
}
int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int n, m, p, q;
	cin >> n >> m;
	for (int i=1; i<=m; i++)
	{
		int u, v, w;
		cin >> u >> v >> w;
		adj[u].push_back({v, w});
		adj[v].push_back({u, w});
		edge.push_back({u, v});
	}
	cin >> p;
	for (int i=1; i<=n; i++)
		dist[i]=1e9;
	for (int i=1; i<=p; i++)
	{
		int u;
		cin >> u;
		dist[u]=0;
		pq.push({0, u});
	}
	while (!pq.empty())
	{
		int num=-pq.top().first, u=pq.top().second;
		pq.pop();
		if (dist[u]<num)
			continue;
		for (int i=0; i<adj[u].size(); i++)
		{
			int v=adj[u][i].first, w=adj[u][i].second;
			if (dist[v]>dist[u]+w)
			{
				dist[v]=dist[u]+w;
				pq.push({-dist[v], v});
			}
		}
	}
	sort(edge.begin(), edge.end(), cmp);
	cin >> q;
	for (int i=1; i<=q; i++)
	{
		int u, v;
		cin >> u >> v;
		s[u].insert(i);
		s[v].insert(i);
	}
	for (int i=1; i<=n; i++)
		par[i]=i;
	for (int i=0; i<edge.size(); i++)
	{
		int u=edge[i].first, v=edge[i].second;
		int paru=findPar(u), parv=findPar(v), num=min(dist[u], dist[v]);
		if (paru==parv)
			continue;
		if (s[paru].size()>s[parv].size())
			swap(paru, parv);
		for (int x:s[paru])
		{
			if (s[parv].count(x))
			{
				ans[x]=num;
				s[parv].erase(x);
			}
			else
				s[parv].insert(x);
		}
		par[paru]=parv;
	}
	for (int i=1; i<=q; i++)
		cout << ans[i] << '\n';
	return 0;
}

Compilation message (stderr)

plan.cpp: In function 'int main()':
plan.cpp:50:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |   for (int i=0; i<adj[u].size(); i++)
      |                 ~^~~~~~~~~~~~~~
plan.cpp:71:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |  for (int i=0; i<edge.size(); i++)
      |                ~^~~~~~~~~~~~

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