Cod sursa(job #3192796)

Utilizator BreabanDanielBreaban Daniel-Vasile BreabanDaniel Data 13 ianuarie 2024 11:18:21
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.77 kb
#include <fstream>
#include <vector>
#include <queue>
#define INF 1000000002
#define NMAX 50002
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
int n,p=1;
bool uz[NMAX];
vector<pair<int,int> >G[NMAX];
int cmin[NMAX];
class ComparVf
{
    public:
    bool operator() (int x,int y)
    {
        return cmin[x]>=cmin[y];
    }
};
priority_queue <pair<int,int>, vector <pair<int,int> >,greater <pair<int,int> > >  H;
void citire();
void dijkstra();
void afisare();
int main()
{
    citire();
    dijkstra();
    afisare();

    return 0;

}
void citire()
{
    int m;
    fin>>n>>m;
    int x,y,c;
    for(int k=0;k<m;k++)
    {
        fin>>x>>y>>c;
        G[x].push_back({y,c});
    }
}
void dijkstra()
{
    int vfmin,x,c;
    pair <int, int> pp;
    pp.first=0;
    pp.second=p;
    H.push(pp);
    for(int i=1;i<=n;i++)
        cmin[i]=INF;
    cmin[p]=0;
    while(!H.empty())
    {
        vfmin=H.top().second;
        H.pop();
        if(cmin[vfmin]==INF)
            break;
        if(!uz[vfmin])
            for(int i=0;i<G[vfmin].size();i++)
                if(!uz[G[vfmin][i].first])
                    {
                        x=G[vfmin][i].first;
                        c=G[vfmin][i].second;
                        if(cmin[x]>cmin[vfmin]+c)
                        {
                            cmin[x]=cmin[vfmin]+c;
                            pp.first=cmin[x];
                            pp.second=x;
                            H.push(pp);
                        }
                    }
        uz[vfmin]=1;

    }
}
void afisare()
{
    for(int i=2;i<=n;i++)
    {
        if(cmin[i]!=INF)
            fout<<cmin[i]<<' ';
        else
            fout<<0<<' ';
    }
}