Submission #411883

#	Time	Username	Problem	Language	Result	Execution time	Memory
411883		pliam	Crocodile's Underground City (IOI11_crocodile)	C++14	100 / 100	628 ms	77608 KiB

crocodile

#include "crocodile.h"
#include <bits/stdc++.h>
using namespace std;
#define MAXN 100005
#define INF (ll)1e18+5
typedef long long ll;
typedef pair<ll,int> pli;//(d2[x],x);

//Dijkstra
ll d1[MAXN],d2[MAXN];
bool used[MAXN];
vector<pair<int,ll>> adj[MAXN];//(to,weight)
priority_queue<pli,vector<pli>,greater<pli>> q;

int travel_plan(int N, int M, int R[][2], int L[], int K, int P[])
{
  for(int i=0;i<M;i++){
    adj[R[i][0]].push_back({R[i][1],L[i]});
    adj[R[i][1]].push_back({R[i][0],L[i]});
  }
  for(int i=0;i<N;i++){
    d1[i]=d2[i]=INF;
    used[i]=false;
  }
  for(int i=0;i<K;i++){
    d1[P[i]]=d2[P[i]]=0;
    q.push({d2[P[i]],P[i]});
  }
  while(!q.empty()){
    int v=q.top().second;
    q.pop();
    if(used[v]) continue;
    used[v]=true;
    for(auto p:adj[v]){
      int to=p.first;
      ll w=p.second;
      if(d2[v]+w<=d1[to]){
        d2[to]=d1[to];
        d1[to]=d2[v]+w;
      }else if(d2[v]+w<d2[to]){
        d2[to]=d2[v]+w;
      }else{
        continue;//d2[to] didn't change
      }
      q.push({d2[to],to});
    }
  }
  return d2[0];
}

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