Submission #123624

#	Time	Username	Problem	Language	Result	Execution time	Memory
123624		deinfreund	Crocodile's Underground City (IOI11_crocodile)	C++14	100 / 100	1053 ms	71908 KiB

crocodile

#include "crocodile.h"
#include <bits/stdc++.h>

using namespace std;
 
vector<vector<int>> conns;
vector<vector<int>> costs;

int travel_plan(int N, int M, int R[][2], int L[], int K, int P[])
{
  conns.resize(N);
  costs.resize(N);
  for (int i = 0; i < M; i++){
    int a = R[i][0];
    int b = R[i][1];
    conns[a].push_back(b);
    conns[b].push_back(a);
    costs[a].push_back(L[i]);
    costs[b].push_back(L[i]);
  }
  const long long big = 1000000000;//100000000000000000LL;
  vector<long long> firstCost(N, big);
  vector<long long> secondCost(N, big);
  priority_queue<pair<long long, int>> pq;
  for (int i = 0; i < K; i++){
    pq.push({0, P[i]});
  }
  vector<bool> visited(N, 0);
  while (!pq.empty()){
    int pos;
    long long cost;
    do{
      pos = pq.top().second;
      cost = -pq.top().first;
      pq.pop();
    }while(visited[pos] && !pq.empty());
    if (visited[pos]) break;
    visited[pos] = 1;
    for (unsigned int i = 0; i < conns[pos].size(); i++){
      if (!visited[conns[pos][i]]){
	long long c = cost + costs[pos][i];
	if (c < secondCost[conns[pos][i]]){
	  if (c < firstCost[conns[pos][i]]){
	    secondCost[conns[pos][i]] = firstCost[conns[pos][i]];
	    firstCost[conns[pos][i]] = c;
	  }else{
	    secondCost[conns[pos][i]] = c;
	  }
	  pq.push({-secondCost[conns[pos][i]], conns[pos][i]});
	}
      }
    }
  }
  return secondCost[0];
}

• Subtask 1: 46 / 46
• Subtask 2: 43 / 43
• Subtask 3: 11 / 11