제출 #897454

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
897454		Muhammad_Aneeq	꿈 (IOI13_dreaming)	C++17	100 / 100	83 ms	18228 KiB

dreaming

#include <vector>
#include <algorithm>
#include <queue>
#include "dreaming.h"
using namespace std;
int const N=1e5+10;
vector<pair<int,int>>nei[N]={};
vector<int>heads;
int vis[N]={};
int cost[N]={};
void dfs(int n)
{
	vis[n]=1;
	for (auto [i,w]:nei[n])
	{
		if (!vis[i])
		{
			dfs(i);
			cost[n]=max(cost[i]+w,cost[n]);
		}
	}
}
bool w1=0;
int dist,root;
void getroot(int n,int pa,int ma)
{
	int mx1=0,mx2=0;
	int ind=n;
	for (auto [i,w]:nei[n])
	{
		if(i!=pa)
		{
			int z=cost[i]+w;
			if (z>mx1)
			{
				mx2=mx1;
				mx1=z;
				ind=i;
			}
			else if (z>mx2)
				mx2=z;
		}
	}
	if (max(mx1,ma)<dist)
	{
		dist=max(mx1,ma);
		root=n;
	}
	for (auto [i,w]:nei[n])
	{
		if (i!=pa)
		{
			if (ind==i)
				getroot(i,n,max(ma,mx2)+w);
			else
				getroot(i,n,max(ma,mx1)+w);
		}
	}
}
void bfs(int n)
{
	queue<pair<int,int>>Q;
	Q.push({n,-1});
	while (Q.size())
	{
		int n,m;
		tie(n,m)=Q.front();
		Q.pop();
		for (auto [i,w]:nei[n])
		{
			if (i!=m)
			{
				cost[i]=cost[n]+w;
				Q.push({i,n});
			}
		}
	}
}
int travelTime(int n, int m, int l, int a[], int b[], int t[])
{
	for (int i=0;i<m;i++)
	{
		nei[a[i]].push_back({b[i],t[i]});
		nei[b[i]].push_back({a[i],t[i]});
	}
	for (int i=0;i<n;i++)
	{
		if (!vis[i])
		{
			heads.push_back(i);
			dfs(i);
		}
	}
	for (int i=0;i<n;i++)
		vis[i]={};
	vector<pair<int,int>>new_head;
	for (auto i:heads)
	{
		dist=1e9+10;
		root=i;
		getroot(i,-1,0);
		new_head.push_back({dist,root});
	}
	sort(begin(new_head),end(new_head));
	reverse(begin(new_head),end(new_head));
	for (int i=1;i<new_head.size();i++)
	{
		nei[new_head[0].second].push_back({new_head[i].second,l});
		nei[new_head[i].second].push_back({new_head[0].second,l});
	}
	for (int i=0;i<n;i++)
		cost[i]=0;
	bfs(new_head[0].second);
	w1=0;
	new_head={};
	for (int i=0;i<n;i++)
	{
		new_head.push_back({cost[i],i});
		cost[i]=0;
	}
	sort(begin(new_head),end(new_head));
	reverse(begin(new_head),end(new_head));
	bfs(new_head[0].second);
	new_head={};
	for (int i=0;i<n;i++)
	{
		new_head.push_back({cost[i],i});
		cost[i]=0;
	}
	sort(begin(new_head),end(new_head));
	reverse(begin(new_head),end(new_head));
	return new_head[0].first;
}

컴파일 시 표준 에러 (stderr) 메시지

dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:106:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  106 |  for (int i=1;i<new_head.size();i++)
      |               ~^~~~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 10 / 10
• Subtask 3: 23 / 23
• Subtask 4: 18 / 18
• Subtask 5: 12 / 12
• Subtask 6: 23 / 23