Cod sursa(job #2499807)

Utilizator FrostfireMagirescu Tudor Frostfire Data 26 noiembrie 2019 19:33:00
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.39 kb
#include <fstream>
#include <iostream>
#include <queue>
#define NMAX 50000
#define inf 2000000000

using namespace std;

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

int n, m, dist[NMAX+10];
bool b[NMAX+10];
priority_queue <pair <int, int>, vector <pair <int, int> >, greater <pair <int, int> > > pq;
vector <pair <int, int> > nod[NMAX+10];

int main()
{
    f >> n >> m;
    for(int i=1; i<=m; i++)
        {   int nod1, nod2, cost;
            f >> nod1 >> nod2 >> cost;
            nod[nod1].push_back(make_pair(cost, nod2));
        }
    pq.push(make_pair(0, 1));
    for(int i=2; i<=n; i++) dist[i] = inf;

    while(!pq.empty())
        {   pair <int, int> a = pq.top();
            pq.pop();
            if(!b[a.second])
                {   b[a.second] = 1;
                    for(int i=0; i<nod[a.second].size(); i++)
                        {   int d = a.first + nod[a.second][i].first;
                            if(d < dist[nod[a.second][i].second])
                                {   dist[nod[a.second][i].second] = d;
                                    pq.push(make_pair(d, nod[a.second][i].second));
                                }
                        }
                }
        }
    for(int i=2; i<=n; i++)
        {   if(dist[i] != inf) g << dist[i] << ' ';
            else g << 0 << ' ';
        }
    g << '\n';
    return 0;
}