Cod sursa(job #3286366)

Utilizator drulealex12Drule Alex Stefan drulealex12 Data 14 martie 2025 09:07:41
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.42 kb
#include <bits/stdc++.h>

using namespace std;

ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");

const int Nmax=50005;
const int oo=(1 << 30);

int n, m;
int d[Nmax];
bool vizitat[Nmax];
vector< pair <int, int> > G[Nmax];

struct comparaDistante
{
    bool operator()(int x, int y)
    {
        return d[x]>d[y];
    }
};

priority_queue <int, vector<int>, comparaDistante> Coada;


void dijkstra(int start)
{
    for(int i=1;i<=n;i++)
    {
        d[i]=oo;
    }
    d[start]=0;
    Coada.push(start);
    vizitat[start]=true;
    while(!Coada.empty())
    {
        int nod=Coada.top();
        Coada.pop();
        vizitat[nod]=false;
        for(size_t i=0;i<G[nod].size();i++)
        {
            int vecin=G[nod][i].first;
            int cost=G[nod][i].second;
            if(d[nod]+cost < d[vecin])
            {
                d[vecin]=d[nod]+cost;
                if(vizitat[vecin]==false)
                {
                    Coada.push(vecin);
                    vizitat[vecin]=true;
                }
            }
        }
    }
}

int main()
{
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int x, y, c;
        fin>>x>>y>>c;
        G[x].push_back(make_pair(y, c));
    }
    dijkstra(1);
    for(int i=2;i<=n;i++)
    {
        if(d[i]!=oo)
        {
            fout<<d[i]<<" ";
        }
        else
            fout<<0<<" ";
    }
}