Submission #243926

#	Time	Username	Problem	Language	Result	Execution time	Memory
243926		kshitij_sodani	Museum (CEOI17_museum)	C++17	0 / 100	396 ms	392184 KiB

museum

#include <bits/stdc++.h>
using namespace std;
typedef int64_t llo;
#define mp make_pair
#define pb push_back
#define a first 
#define b second
//#define endl '\n'

int n,k,x;
vector<pair<int,int>> adj[10001];
int ss[10001];
int tt[10001];
void dfs(int no,int par2=-1){
	tt[no]=0;
	ss[no]=1;
	for(auto j:adj[no]){
		if(j.a==par2){
			continue;
		}
		dfs(j.a,no);
		tt[no]+=tt[j.a]+j.b;
		ss[no]+=ss[j.a];
	}
}
int dp[100001];
int tot=0;
int cot=0;
int ans=1e9;
int back[10001][10001];
void dfs2(int no,int par2=-1,int su=0){
	cot+=1;
	if(cot>=k){
		ans=min(ans,(tot-dp[cot-k])*2-su);
	}
	for(int i=ss[no]-1;i<=n;i++){
		if(dp[i-ss[no]+1]==-1){
			back[no][i]=-1;
			continue;
		}
		back[no][i]=max(dp[i],tt[no]+dp[i-ss[no]+1]);;
	}

	for(auto j:adj[no]){
		if(j.a==par2){
			continue;
		}
		tot+=j.b;
		dfs2(j.a,no,su+j.b);
	}
	for(int i=n;i>=ss[no]-1;i--){
		dp[i]=max(dp[i],back[no][i]);
		/*if(dp[i-ss[no]+1]==-1){
			continue;
		}
		dp[i]=max(dp[i],tt[no]+dp[i-ss[no]+1]);*/
	}
}

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cin>>n>>k>>x;
	for(int i=0;i<n-1;i++){
		int aa,bb,cc;
		cin>>aa>>bb>>cc;
		aa--;
		bb--;
		adj[aa].pb({bb,cc});
		adj[bb].pb({aa,cc});
	}
	for(int i=1;i<=n;i++){
		dp[i]=-1;
	}
	dfs(x);
	dfs2(x);
	cout<<ans<<endl;




	return 0;
}

• Subtask 1: 0 / 20
• Subtask 2: 0 / 25
• Subtask 3: 0 / 35
• Subtask 4: 0 / 20