제출 #104088

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
104088		pedro_sponchiado	꿈 (IOI13_dreaming)	C++17	0 / 100	113 ms	18600 KiB

dreaming

#include "dreaming.h"
#include<bits/stdc++.h>
using namespace std;
const int maxn=100010;

int n, m, l;
vector<int> adj[maxn], peso[maxn];

int raio1, raio2;

int dist[maxn], pai[maxn];
int marc[maxn];
int maxi, maior;

void dfs(int u, int t){
	marc[u]=1;
	
	if(maxi<=dist[u]){
		maior=u;
		maxi=dist[u];
	}
	
	for(int i=0; i<adj[u].size(); i++){
		int v=adj[u][i];
		if(v!=pai[u]){
			pai[v]=u;
			dist[v]=dist[u]+peso[u][i];
			dfs(v, t);
		}
	}
	if(t) pai[u]=-1;
	return;
}

pair<int, int> proximos_raios(int a){
	int maxi=0;
	dist[a]=0;
	pai[a]=-1;
	dfs(a, 1);
	
	int pr=maior;
	dist[maior]=0;
	maxi=0;
	dfs(maior, 0);
	
	int at=maior;
	pair<int, int> resp=make_pair(0, dist[maior]);
	
	while(at!=pr){
		if(max(resp.first, resp.second)> max(dist[at], dist[maior]-dist[at]) ){
			resp=make_pair(dist[at], dist[maior]-dist[at]);
		}
		at=pai[at];	
	}
	if(resp.first>resp.second) swap(resp.first, resp.second);
	
	return resp;
}


int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
	
    n=N; m=M; l=L;
    
    for(int i=0; i<m; i++){
    	adj[A[i]].push_back(B[i]);
		adj[B[i]].push_back(A[i]);
		peso[A[i]].push_back(T[i]);
		peso[B[i]].push_back(T[i]);
	}
	raio1=-1;
	for(int i=0; i<n; i++){
		if(marc[i]==0){
			pair<int, int> p=proximos_raios(i);
			
		//	printf("%d: %d %d %d %d\n", i, raio1, raio2, p.first, p.second);
			if(raio1==-1){
				raio1=p.first;
				raio2=p.second;
				continue;
			}
			
			if(raio2>p.second){
				raio1=raio2;
				raio2=max(p.second+l, raio1);
			}
			
			else{
				raio1=p.second;
				raio2=max(raio2+l, p.first);
			}
			
			if(raio1>raio2) swap(raio1, raio2);
		}
	}
	
	return raio1+raio2;
}

컴파일 시 표준 에러 (stderr) 메시지

dreaming.cpp: In function 'void dfs(int, int)':
dreaming.cpp:23:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0; i<adj[u].size(); i++){
               ~^~~~~~~~~~~~~~
dreaming.cpp: In function 'std::pair<int, int> proximos_raios(int)':
dreaming.cpp:36:6: warning: variable 'maxi' set but not used [-Wunused-but-set-variable]
  int maxi=0;
      ^~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 10
• Subtask 3: 0 / 23
• Subtask 4: 0 / 18
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23