Cod sursa(job #2856501)

Utilizator Rares1707Suchea Rares-Andrei Rares1707 Data 23 februarie 2022 22:30:32
Problema Algoritmul lui Dijkstra Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 2.39 kb
#include <iostream>
#include <fstream>
#include <queue>
//#include <set>
#include <vector>
using namespace std;

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

const int MAX = (1 << 30);

int n, m;
int distanta[50005];
bool inclusInHeap[50005];

vector < pair < int, int > > legaturi[50005];

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

priority_queue < int, vector < int >, compara > heap;

//set < int > heap;

/*int DistantaMinima()
{
    int minn = 20005, indiceMin;
    for (int i = 1; i <= n; i++)
    {
        if (inclusInHeap[i] == false &&
            (distanta[i] < minn || distanta[i] == -1) )
        {
            minn = distanta[i];
            indiceMin = i;
        }
    }
    return indiceMin;
}*/

void Citire()
{
    fin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        int x, y, cost;
        fin >> x >> y >> cost;
        legaturi[x].push_back(make_pair(y, cost));
    }

}

void Dijkstra (int nodStart)
{
    for (int i = 1; i <= n; i++)
    {
        distanta[i] = MAX;
    }

    distanta[nodStart] = 0;

    heap.push(nodStart);
    //heap.insert(nodStart);
    inclusInHeap[nodStart] = true;

    while(!heap.empty())
    {
        int nodCurent = heap.top();
        heap.pop();
        //int nodCurent = *heap.begin();
        //heap.erase(heap.begin());

        inclusInHeap[nodCurent] = false;

        for (unsigned int i = 0; i < legaturi[nodCurent].size(); i++)
        {
            int vecin = legaturi[nodCurent][i].first;
            int cost = legaturi[nodCurent][i].second;

            if (distanta[nodCurent] + cost < distanta[vecin])
            {
                distanta[vecin] = distanta[nodCurent] + cost;
                if (inclusInHeap[vecin] == false);
                {
                    heap.push(vecin);
                    //heap.insert(vecin);
                    inclusInHeap[vecin] = true;
                }
            }
        }
    }
}

void Afisare()
{
    for (int i = 2; i <= n; i++)
    {
        if (distanta[i] != MAX)
        {
            fout << distanta[i] << ' ';
        }
        else
        {
            fout << "0 ";
        }
    }
    fout << '\n';
    fin.close();
    fout.close();
}

int main()
{
    Citire();
    Dijkstra(1);
    Afisare();
}