Cod sursa(job #1059154)

Utilizator pulseOvidiu Giorgi pulse Data 16 decembrie 2013 11:49:32
Problema Algoritmul lui Dijkstra Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.31 kb
#include <fstream>
#define NMAX 50002
#define INF 0x3f3f3f3f

using namespace std;

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

int n, m, gmax, d[NMAX], q[NMAX];

struct graf
{
    int nod, cost;
    graf *next;
}*a[NMAX];

void add (int where, int what, int cost)
{
    graf *q=new graf;
    q->nod=what;
    q->cost=cost;
    q->next=a[where];
    a[where]=q;
}

void read ()
{
    fin>>n>>m;
    for (int i=1, nod1, nod2, cost; i<=m; ++i)
    {
        fin>>nod1>>nod2>>cost;
        add (nod1, nod2, cost);
    }
}

void dijkstra ()
{
    for (int i=2; i<=n; ++i)
        d[i]=INF;
    int min, pmin=0;
    for (int i=1; i<=n; ++i)
    {
        min=INF;
        for (int j=1; j<=n; ++j)
        {
            if (d[j] < min && !q[j])
            {
                min=d[j];
                pmin=j;
            }
        }
        q[pmin]=1;
        graf *t=a[pmin];
        while (t)
        {
            if (d[t->nod] > d[pmin] + t->cost)
                d[t->nod]=d[pmin] + t->cost;
            t=t->next;
        }
    }
}

int main ()
{
    read ();
    dijkstra ();
    for (int i=2; i<=n; ++i)
        if (d[i] == INF)
            fout<<0<<" ";
        else
            fout<<d[i]<<" ";
    fin.close(); fout.close();
    return 0;
}