Cod sursa(job #2567055)

Utilizator costin72Ion Costin costin72 Data 3 martie 2020 14:48:30
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.59 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#include <utility>

using namespace std;

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

const int NMAX = 50004, oo = (1 << 30);

int n, m;

vector<int> d(NMAX);

vector<bool> inCoada(NMAX);

vector<vector<pair<int, int>>> adj(NMAX);

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

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

void init()
{
    int i;
    fin >> n >> m;
    for(i = 1; i <= m; i++)
    {
        int x, y, dist;
        fin >> x >> y >> dist;
        adj[x].push_back(make_pair(y, dist));
    }
    for(i = 1; i <= n; i++)
        d[i] = oo;
}

void dijkstra(int nodStart)
{
    d[nodStart] = 0;
    Coada.push(nodStart);
    inCoada[nodStart] = true;
    while(!Coada.empty())
    {
        int nodCurent = Coada.top();
        Coada.pop();
        inCoada[nodCurent] = false;
        int i, z = adj[nodCurent].size();
        for(i = 0; i < z; i++)
        {
            int vecin = adj[nodCurent][i].first, cost = adj[nodCurent][i].second;
            if(d[vecin] > d[nodCurent] + cost)
            {
                d[vecin] = d[nodCurent] + cost;
                if(inCoada[vecin] == false)
                {
                    inCoada[vecin] = true;
                    Coada.push(vecin);
                }
            }
        }
    }
}

void afisare()
{
    int i;
    for(i = 2; i <= n; i++)
    {
        if(d[i] != oo)
            fout << d[i] << " ";
        else
            fout <<"0 ";
    }
}

int main()
{
    init();
    dijkstra(1);
    afisare();
}