Cod sursa(job #2264920)

Utilizator mihailrazMihail Turcan mihailraz Data 20 octombrie 2018 12:55:49
Problema Algoritmul lui Dijkstra Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.24 kb
#include <fstream>
#include <vector>
#include <queue>
#define INF 2000000000
#define NMAX 50000

using namespace std;
ifstream fi("dijkstra.in");
ofstream fo("dijkstra.out");
int n, m;
int DIST[NMAX+5], VIZ[NMAX+5];
vector <pair <int, int> > G[NMAX+5];
priority_queue <pair<int, int> > PQ;

void citire(void)
{
    int x, y, c;
    fi>>n>>m;
    for(int i=1; i<=m; i++)
    {
        fi>>x>>y>>c;
        G[x].push_back({c, y});
    }
}

void dijkstra(void)
{
    int nod, nods, cost, costs;
    for(int i=2; i<=n; i++)
        DIST[i]=INF;
    PQ.push({0, 1});
    DIST[1]=0;
    while(!PQ.empty())
    {
        nod=PQ.top().second;
        cost=-PQ.top().first;
        PQ.pop();
        if(VIZ[nod])
           continue;
        VIZ[nod]=1;
        for(auto vec:G[nod])
        {
            nods=vec.second;
            costs=-vec.first;
            if(DIST[nods]>DIST[nod]+costs)
            {
                DIST[nods]=DIST[nod]+costs;
                PQ.push({-costs, nods});
            }
        }
    }
}

void afisare(void)
{
    for(int i=2; i<=n; i++)
        if(DIST[i]==INF)
            fo<<0<<" ";
        else
            fo<<DIST[i]<<" ";
}

int main()
{
    citire();
    dijkstra();
    afisare();
    fi.close();
    fo.close();
    return 0;
}