Cod sursa(job #887931)

Utilizator boby301Bogdan Bacila boby301 Data 24 februarie 2013 10:08:25
Problema Algoritmul lui Dijkstra Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 1.36 kb
#include <iostream>
#include <fstream>
using namespace std;
#define NMAX 1005
#define INFINIT 1005

ifstream f("dijkstra.in");
ofstream g("dijkstra.out");

int n,m,x,y,z,i,j;
int a[NMAX][NMAX];

void dijkstra(int x0)
{
    int i,min, k, ok;
    int viz[NMAX], d[NMAX], tata[NMAX];
    for (i = 1; i<=n; i++) {
        d[i] = a[x0][i];
        tata[i] = x0;
        viz[i] = 0;
    }
    tata[x0] = 0;
    viz[x0] = 0; ok = 1;
    while (ok==1) {
        min = INFINIT;
        for (i = 1; i<=n; i++)
            if ((viz[i]==0) && (min>d[i]))
            {
                min = d[i];
                k = i;
            }
        if (min != INFINIT)
        {
            viz[k] = 1;
            for (i = 1; i<=n; i++)
               if ((viz[i]==0) && (d[i]>d[k]+a[k][i]))
               {
                   d[i] = d[k]+a[k][i];
                   tata[i] = k;
               }
        }
        else ok = 0;
    }
    for (i=2;i<=n;i++)
    {
        if (d[i]==INFINIT)
        {
          g<<0<<" ";
        }
        else
        {
          g<<d[i]<<" ";
        }
    }
}


int main()
{
    f>>n>>m;
    for (i=1;i<=m;i++){f>>x>>y>>z; a[x][y]=z;}

     for (i=1;i<=n;i++)
    {
        for (j=1;j<=n;j++)
        {
            if (a[i][j]==0)
            {a[i][j]=INFINIT;}
        }
    }

    dijkstra(1);
}