Cod sursa(job #2270383)

Utilizator IVVladIon Vlad Vasile IVVlad Data 27 octombrie 2018 10:47:32
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.44 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
const int NMax = 50005;
const int oo = (1 << 30);
int N,M;
int D[NMax];
bool viz[NMax];
vector < pair <int,int> > G[NMax];
struct compara
{
    bool operator() (int x,int y)
    {
        return D[x]>D[y];
    }
};
priority_queue<int, vector<int>, compara> coada;
void citire()
{
    f>>N>>M;
    for(int i=1; i<=M; i++)
    {
        int x,y,c;
        f>>x>>y>>c;
        G[x].push_back(make_pair(y,c));
    }
}
void Dijkstra(int nod)
{
    for(int i=1; i<=N; i++)
        D[i]=oo;
    D[nod]=0;
    coada.push(nod);
    viz[nod]=1;
    while(!coada.empty())
    {
        int nodcurent=coada.top();
        coada.pop();
        viz[nodcurent]=0;
        for(size_t i=0; i<G[nodcurent].size(); i++)
        {
            int vecin=G[nodcurent][i].first;
            int cost=G[nodcurent][i].second;
            if(D[vecin]>D[nodcurent]+cost)
            {
                D[vecin]=D[nodcurent]+cost;
                if(viz[vecin]==0)
                {
                    viz[vecin]=1;
                    coada.push(vecin);
                }
            }
        }
    }
}
void afisare()
{
    for(int i=2; i<=N; i++)
    {
        if(D[i]!=oo)g<<D[i]<<" ";
        else g<<0<<" ";
    }
}
int main()
{
    citire();
    Dijkstra(1);
    afisare();
    return 0;
}