Cod sursa(job #996809)

Utilizator DaniEsDani Stetcu DaniEs Data 12 septembrie 2013 17:54:21
Problema Algoritmul lui Dijkstra Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.31 kb
#include <fstream>
#include <vector>
#define NMax 50005
#define oo 2000000000
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
int N,M,D[NMax],S[NMax];
vector < pair<int,int> > G[NMax];

void Read()
{
    fin>>N>>M;
    for(int i=1;i<=M;i++)
        {
            int x,y,c;
            fin>>x>>y>>c;
            G[x].push_back(make_pair(y,c));
        }
}
inline void InitDijkstra (int Start)
{
    for(int i=2;i<=N;i++)
        D[i]=oo;
}
int ComputeMin()
{
    int Min=oo,poz;
    for(int i=1;i<=N;i++)
        if((D[i]<Min) &&(!S[i]))
            {
                Min=D[i];
                poz=i;
            }
    return poz;
}
inline void Relax(int Nod,int Vecin,int Cost)
{
   if(D[Vecin]>D[Nod]+Cost)
      D[Vecin]=D[Nod]+Cost;
}
void Dijkstra(int Start)
{
    InitDijkstra(Start);

    for(int i=1;i<=N;i++)
        {
            int Nod=ComputeMin();
            S[Nod]=1;
            for(unsigned int j=0;j<G[Nod].size();j++)
                Relax(Nod,G[Nod][j].first,G[Nod][j].second);
        }
}
void Print()
{
    for(int i=2;i<=N;i++)
        {
            if(D[i]==oo)
                D[i]=0;
            fout<<D[i]<<" ";
        }
    fout<<'\n';
}
int main()
{
    Read();
    Dijkstra(1);
    Print();
    return 0;
}