Submission #924943

#	Time	Username	Problem	Language	Result	Execution time	Memory
924943		8pete8	Parkovi (COCI22_parkovi)	C++17	110 / 110	1342 ms	43048 KiB

Main

#include<iostream>
#include<stack>
#include<map>
#include<vector>
#include<string>
#include<unordered_map>
#include <queue>
#include<cstring>
#include<cassert>
#include<limits.h>
#include<cmath>
#include<set>
#include<numeric> //gcd(a,b)
#include<algorithm>
#include<bitset> 
#include<stack>
using namespace std;
#define ll long long
#define f first
#define endl "\n"
#define s second
#define pii pair<int,int>
#define pppiiii pair<pii,pii>
#define ppii pair<int,pii>
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define pb push_back
#define mp make_pair
#define lb lower_bound
#define ub upper_bound
#define fastio ios::sync_with_stdio(false);cin.tie(NULL);
#define int long long
const int mod=1e9+7,mxn=2e5+5,lg=30,inf=1e18,minf=-1e18,Mxn=100000,root=700;
void setIO(string name){		
	ios_base::sync_with_stdio(0); cin.tie(0);		
	freopen((name+".in").c_str(),"r",stdin);		
	freopen((name+".out").c_str(),"w",stdout);	
}	
int n,k,mid;
vector<pii>adj[mxn+10];
int cnt=0;
int dist[mxn+10],last[mxn+10],seen[mxn+10];
vector<int>path;
void putmx(pii &a,int k){
	if(dist[a.f]<dist[k])swap(a.f,a.s),a.f=k;
	else if(dist[a.s]<dist[k])a.s=k;
}
void check(int cur,int p,int up){
	for(auto i:adj[cur])if(i.f!=p)check(i.f,cur,i.s);
	seen[cur]=last[cur]=-1;
	int c=0;
	for(auto i:adj[cur])if(i.f!=p){
		c++;
		if(seen[i.f]!=-1&&(seen[cur]==-1||dist[seen[cur]]<dist[seen[i.f]]))seen[cur]=seen[i.f];
		if(last[i.f]!=-1&&(last[cur]==-1||dist[last[cur]]>dist[last[i.f]]))last[cur]=last[i.f];
	}
	if(seen[cur]!=-1&&last[cur]!=-1&&dist[seen[cur]]+dist[last[cur]]-2*dist[cur]<=mid)seen[cur]=-1;
	if(c==0||(dist[last[cur]]-dist[cur]>mid&&seen[cur]==-1))seen[cur]=cur;
	if(seen[cur]!=-1&&dist[seen[cur]]-dist[cur]+up>mid)last[cur]=cur,cnt++,path.pb(cur),seen[cur]=-1;
	if(seen[cur]!=-1&&cur==1)last[cur]=cur,cnt++,path.pb(cur),seen[cur]=-1;
}
void getdist(int cur,int p){for(auto i:adj[cur])if(i.f!=p)dist[i.f]=dist[cur]+i.s,getdist(i.f,cur);}
bool on[mxn+10];
int32_t main(){
	//setIO("mooriokart");
	fastio
	cin>>n>>k;
	int l=0,r=0;
	for(int i=0;i<n-1;i++){
		int a,b,c;cin>>a>>b>>c;
		r+=c;
		adj[a].pb({b,c});
		adj[b].pb({a,c});
	}
	getdist(1,-1);
	pair<int,vector<int>>ans={inf,{0}};
	while(l<=r){
		mid=l+(r-l)/2;
		path.clear();
		cnt=0;
		check(1,-1,0);
		if(cnt<=k)r=mid-1,ans=min(ans,{mid,path});
		else l=mid+1;
	}
	for(auto i:ans.s)on[i]=1;
	cnt=k-ans.s.size();
	for(int i=1;i<=n;i++)if(!on[i]&&cnt)ans.s.pb(i),cnt--;
	cout<<ans.f<<'\n';
	for(auto i:ans.s)cout<<i<<" ";
}

Compilation message (stderr)

Main.cpp: In function 'void setIO(std::string)':
Main.cpp:36:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |  freopen((name+".in").c_str(),"r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:37:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |  freopen((name+".out").c_str(),"w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 30 / 30
• Subtask 4: 60 / 60