Submission #1014339

#	Time	Username	Problem	Language	Result	Execution time	Memory
1014339		lalig777	Traffic (IOI10_traffic)	C++14	50 / 100	305 ms	178580 KiB

traffic

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long int ll;
const int MAXN=1e5+5;
struct diam{
  long long int max1=0;
  long long int max2=0;
};

vector<vector<int>> listaAdy;
vector<diam>dp;
int n;
ll res=1e18;
int answer=-1;

void dfs1(int nodo, int padre, int P[]){
  for(int v: listaAdy[nodo]){
    if (v==padre) continue;
    dfs1(v, nodo, P);
    if (dp[nodo].max1<dp[v].max1){
      dp[nodo].max2=dp[nodo].max1;
      dp[nodo].max1=dp[v].max1;
    }else if (dp[nodo].max2<dp[v].max1){
      dp[nodo].max2=dp[v].max1;
    }
  }dp[nodo].max1+=P[nodo];
  dp[nodo].max2+=P[nodo];
  return;
}

void dfs2(int nodo, int padre, ll maxi, int P[]){
  ll maxini=maxi;
  if (res>max(maxi, dp[nodo].max1-P[nodo])){
    res=max(maxi, dp[nodo].max1-P[nodo]);
    answer=nodo;
  }
  for(int v: listaAdy[nodo]){
    if(v==padre) continue;
    if(dp[nodo].max1==dp[v].max1+P[nodo]){
      maxi=max(maxini+P[nodo], dp[nodo].max2);
    }else{
      maxi=max(maxini+P[nodo], dp[nodo].max1);
    }
    dfs2(v, nodo, maxi, P);
  }return;
}

int LocateCentre(int N, int P[], int S[], int D[]) {
  listaAdy.clear();
  listaAdy.resize(N);
  dp.clear();
  dp.resize(N);
  for (int i=0; i<N-1; i++){
    listaAdy[S[i]].push_back(D[i]);
    listaAdy[D[i]].push_back(S[i]);
  }dfs1(0,0,P);
  dfs2(0,0,0,P);
  return answer;
}

/*int main(){
  int N, P[MAXN], S[MAXN], D[MAXN];
  cin>>N;
  for (int i=0; i<N; i++) cin>>P[i];
  for (int i=0; i<N-1; i++){
    cin>>S[i]>>D[i];
  }
  cout<<LocateCentre(N, P, S, D)<<endl;
  cout<<res<<endl;
  return 0;
}*/

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