Cod sursa(job #2377121)

Utilizator My_Road_To_ONIAndrei Panainte My_Road_To_ONI Data 8 martie 2019 21:55:35
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.49 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);

struct Graf
{
    int nod, cost;
    inline bool operator < (const Graf &A) const
    {
        return cost > A.cost;
    }
};

priority_queue < Graf > Q;
vector < pair < int, int > > L[Nmax];

int dist[Nmax], n, m;
bool viz[Nmax];

void Read()
{
    int i, x, y, c;
    fin >> n >> m;
    for (i = 1 ; i <= m ; i++)
    {
        fin >> x >> y >> c;
        L[x] . push_back({y, c});
    }
    fin.close();
}

void Init()
{
    int i;
    for(i = 1 ; i <= n ; i++) dist[i] = oo;
}

void Dijkstra()
{
    Graf w, w1;
    dist[1] = 0;
    w = {1, 0};
    Q.push(w);
    while (!Q.empty())
    {
        w = Q.top();
        Q.pop();
        if (!viz[w.nod])
        {
            viz[w.nod] = true;
            for (auto k : L[w.nod])
            {
                if (dist[k.first] > dist[w.nod] + k.second)
                {
                    dist[k.first] = dist[w.nod] + k.second;
                    w1 = {k.first, dist[k.first]};
                    Q.push(w1);
                }
            }
        }
    }
}

void Write()
{
    int i;
    for (i = 2 ; i <= n ; i++)
        if (dist[i] == oo) fout << "0 ";
        else fout << dist[i] << " ";
    fout << "\n";
    fout.close();
}

int main()
{
    Read();
    Init();
    Dijkstra();
    Write();
    return 0;
}