Cod sursa(job #2571326)

Utilizator dsandru89Sandru Daniel Cornel dsandru89 Data 4 martie 2020 22:19:45
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.4 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");

const int oo=(1<<30),nMAX=50005;
int n,m;
int d[nMAX];
bool inCoada[nMAX];

vector <pair<int,int> >A[nMAX];

struct compara{
    bool operator()(int a,int b){
       return d[a]>d[b];
    }
};

priority_queue <int,vector<int>,compara> coada;

void citire(){
      for(int i=1;i<=m;i++){
        int x,y,c;
        fin>>x>>y>>c;
        A[x].push_back(make_pair(y,c));
      }
}

void dijkstra(int nodStart)
{
 for(int i=1;i<=n;i++){d[i]=oo;}
     coada.push(nodStart);
     d[nodStart]=0;
     inCoada[nodStart]=true;
     while(!coada.empty()){
       int nodCurent=coada.top();
       coada.pop();
       inCoada[nodCurent]=false;
       for(size_t i=0;i<A[nodCurent].size();i++){
            int vecin=A[nodCurent][i].first;
            int cost=A[nodCurent][i].second;
            if(d[vecin]>d[nodCurent]+cost){d[vecin]=d[nodCurent]+cost;
                   if(inCoada[vecin]==false){
                      coada.push(vecin);
                      inCoada[vecin]=true;
                   }
            }
       }
     }
}
int main(){
    fin>>n>>m;
    citire();
    dijkstra(1);
    for(int i=2;i<=n;i++)
        if(d[i]!=oo)fout<<d[i]<<" ";
      else fout<<"0 ";
      fout.close();fin.close();
 return 0;
}