Submission #638418

#	Time	Username	Problem	Language	Result	Execution time	Memory
638418		ojoConmigo	Traffic (IOI10_traffic)	C++17	0 / 100	1 ms	212 KiB

traffic

#include "traffic.h"
#include <bits/stdc++.h>
using namespace std;

vector<vector<int>> g;
vector<long long> fir,sec,ans,subarbol;

void dfs1(int nodo, int p, int pp[]){
   for(int v : g[nodo]){
      if(v == p)continue;
      dfs1(v,nodo,pp);
      subarbol[nodo] += subarbol[v] + pp[v];
      if(subarbol[v] + pp[v] > fir[nodo]){
         sec[nodo] = fir[nodo];
         fir[nodo] = subarbol[v] + pp[v];
      }else if(subarbol[v] + pp[v] > sec[nodo]){
         sec[nodo] = subarbol[v] + pp[v];
      }
   }
   //cout << nodo << " " << fir[nodo] << " " << sec[nodo] << endl;
}

void dfs2(int nodo, int p, long long cont, int pp[]){
   ans[nodo] = max(cont,fir[nodo]);
   for(int v : g[nodo]){
      if(v == p)continue;
      if(subarbol[v] + pp[v] == fir[nodo]) dfs2(v,nodo,(cont > sec[nodo] ? cont + subarbol[nodo] - subarbol[v] : sec[nodo] + pp[nodo]),pp);
      else dfs2(v,nodo,cont + subarbol[nodo] - subarbol[v], pp);
   }
}

int LocateCentre(int N, int pp[], int S[], int D[]) {
   g.resize(N);
   for(int i=0; i<N-1; i++){
      int x,y;
      x = S[i]; y = D[i];
      //cout << x << " " << y << endl;
      g[x].push_back(y);
      g[y].push_back(x);
   }
   fir.assign(N,0);
   sec.assign(N,0);
   subarbol.assign(N,0);
   ans.resize(N);
   dfs1(0,-1,pp);
   dfs2(0,-1,0,pp);
   int arena = 0;
   long long congestion = 2e9 + 1;
   for(int i=0; i<N; i++){
      //cout << i << " " << ans[i] << " " << congestion << endl;
      if(ans[i] < congestion){
         congestion = ans[i];
         arena = i;
      }
   }
   //cout << arena << endl;
   return arena;
}

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