Cod sursa(job #2390259)

Utilizator alex.cojocaruAlex Cojocaru alex.cojocaru Data 27 martie 2019 21:13:31
Problema Algoritmul lui Dijkstra Scor 30
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.34 kb
#include <iostream>
#include <stdio.h>
#include <queue>

#define NMAX 50000
#define MMAX 250000
#define INFINIT 1000000000

using namespace std;

struct muchie {
  int u ;
  int v ;
  int cost ;
  bool operator < ( const muchie& aux) const {
    return cost > aux.cost ;
  }
};
struct nod {
  int v ;
  int cost ;
};

int dist [ NMAX + 1 ] ;
priority_queue <muchie> q ;
vector <nod> g [ NMAX + 1 ] ;

void dijkstra (int sursa) {
  dist[sursa] = 0 ;
  for (auto y : g[sursa] )
    q.push({sursa, y.v, y.cost}) ;
  while (!q.empty()) {
    int dela = q.top().u ;
    int catre = q.top().v ;
    int cost = q.top().cost ;
    q.pop() ;
    if (dist[catre] == INFINIT ) {
      dist[catre] = dist[dela] + cost ;
      for (auto y : g[catre])
        q.push({catre, y.v, y.cost}) ;
    }
  }
}

int main() {

  FILE *fin, *fout ;
  fin = fopen ("dijkstra.in", "r" ) ;
  fout = fopen ("dijkstra.out", "w" ) ;
  int n, m, i, a, b, cost ;
  fscanf (fin, "%d%d", &n, &m ) ;
  for (i = 0 ; i < m ; i++ ) {
    fscanf (fin, "%d%d%d", &a, &b, &cost ) ;
    g[a].push_back({b, cost}) ;
  }
  for (i = 1 ; i <= n ; i++ )
    dist[i] = INFINIT ;
  dijkstra(1) ;
  for (i = 2 ; i <= n ; i++ ) {
    if (dist[i] == INFINIT )
      fprintf (fout, "%d ", 0 ) ;
    else
      fprintf (fout, "%d ", dist[i] ) ;
  }
  return 0;
}