Cod sursa(job #2657273)

Utilizator Florinos123Gaina Florin Florinos123 Data 10 octombrie 2020 10:41:29
Problema Algoritmul lui Dijkstra Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.34 kb
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

ifstream f ("dijkstra.in");
ofstream g ("dijkstra.out");

const int nmax = 50005;

const int inf =  2e9;

int n, m;

int rez[nmax];

bool inq[nmax];

vector < pair < int, int > > v[nmax];

queue < int > coada;

void Dijkstra (int start)
{
    for (int i=1; i<=n; i++)
        rez[i] = inf;
    rez[start] = 0;

    coada.push(start);
    inq[start] = 1;

    while (!coada.empty())
    {
        int nod = coada.front();
        int lg = v[nod].size();
        inq[nod] = 0;
        coada.pop();

        for (int i=0; i<lg; i++)
        {
            int vecin = v[nod][i].first;
            int cost = v[nod][i].second;

            if (rez[nod] + cost < rez[vecin])
            {
                rez[vecin] = rez[nod] + cost;

                if (!inq[vecin])
                {
                    inq[vecin] = 1;
                    coada.push(vecin);
                }
            }
        }
    }
}

int main()
{
    f >> n >> m;

    while (m --)
    {
        int x, y, c;
        f >> x >> y >> c;
        v[x].push_back(make_pair(y, c));
    }

    Dijkstra(1);

    for (int i=2; i<=n; i++)
    {
        if (rez[i] == inf)
            g << 0 << " ";
        else g << rez[i] << " ";
    }

    return 0;
}