Submission #854941

#	Time	Username	Problem	Language	Result	Execution time	Memory
854941		Wansur	Closing Time (IOI23_closing)	C++17	0 / 100	1045 ms	30796 KiB

closing

#include <vector>
#include<bits/stdc++.h>
#define f first
#define s second
 
using namespace std;
const int mx=2e5+12;
 
vector<pair<int,long long>> g[mx];
long long d1[mx];
long long d2[mx];
long long n,k;
 
void dfs(int v,int p,bool ok){
	for(auto To:g[v]){
		int to=To.f,w=To.s;
		if(to==p){
			continue;
		}
		if(ok){
			d2[to]=d2[v]+w;
		}
		else{
			d1[to]=d1[v]+w;
		}
		dfs(to,v,ok);
	}
}
 
int max_score(int N, int x, int y, long long K, std::vector<int> U,std::vector<int> V, std::vector<int> W){
	n=N,k=K;
	for(int i=0;i<n;i++){
		g[i].clear();
		d1[i]=d2[i]=0;
	}
	for(int i=0;i<n-1;i++){
		g[V[i]].push_back({U[i],W[i]});
		g[U[i]].push_back({V[i],W[i]});
	}
	dfs(x,-1,0);
	dfs(y,-1,1);
	long long ans=0;
	long long sum=0,len=d1[y],cnt=2*(y-x+1);
	for(int i=x;i<=y;i++){
		sum+=max(d1[i],d2[i]);
	}
	vector<long long> v;
	for(int i=0;i<x;i++){
		v.push_back(d1[i]);
	}
	for(int i=y+1;i<n;i++){
		v.push_back(d2[i]);
	}
	sort(v.begin(),v.end());
	for(int i=0;i<v.size();i++){
		if(sum+v[i]<=k){
			sum+=v[i];
			cnt++;
		}
	}
	if(sum<=k){
		cnt+=min(n-(y-x+1),(k-sum)/len);
		ans=cnt;
	}
	for(int l=x;l<y;l++){
		for(int r=x+1;r<=y;r++){
			long long sum=0,cnt=0;
			for(int i=0;i<n;i++){
				long long t=0;
				if(i<=l){
					cnt++;
					t=d1[i];
				}
				if(i>=r){
					t=max(t,d2[i]);
					cnt++;
				}
				sum+=t;
			}
			if(sum<=k){
				ans=max(ans,cnt);
			}
		}
	}
	cnt=0,sum=0;
	v.clear();
	for(int i=0;i<n;i++){
		v.push_back(d1[i]);
	}
	sort(v.begin(),v.end());
	for(long long x:v){
		if(sum+x<=k){
			sum+=x;
			cnt++;
		}
	}
	ans=max(ans,cnt);
	cnt=sum=0;
	v.clear();
	for(int i=0;i<n;i++){
		v.push_back(d2[i]);
	}
	sort(v.begin(),v.end());
	for(long long x:v){
		if(sum+x<=k){
			sum+=x;
			cnt++;
		}
	}
	ans=max(ans,cnt);
	return ans;
}

Compilation message (stderr)

closing.cpp: In function 'int max_score(int, int, int, long long int, std::vector<int>, std::vector<int>, std::vector<int>)':
closing.cpp:55:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |  for(int i=0;i<v.size();i++){
      |              ~^~~~~~~~~

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 0 / 9
• Subtask 3: 0 / 12
• Subtask 4: 0 / 14
• Subtask 5: 0 / 9
• Subtask 6: 0 / 11
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 17