Cod sursa(job #2523717)

Utilizator Cosmin3105Cosmin Colceru Cosmin3105 Data 14 ianuarie 2020 17:53:17
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.55 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

const int NMAX = 50005;
const int INF = (1 << 31) - 1;

int n, m;
int d[NMAX];
bool inCoada[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 nodInitial)
{
    for(int i = 1; i <= n; i++)
        d[i] = INF;
    d[nodInitial] = 0;
    coada.push(nodInitial);
    inCoada[nodInitial] = true;
    while(!coada.empty()){
        int nodCurent = coada.top();
        coada.pop();
        inCoada[nodCurent] = false;

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

            if(d[nodCurent] + cost < d[vecin]){
                d[vecin] = d[nodCurent] + cost;
                if(inCoada[vecin] == false){
                    coada.push(vecin);
                    inCoada[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] != INF)
            fout << d[i] << " ";
        else
            fout << "0 ";
    }

    return 0;
}