Cod sursa(job #2198120)

Utilizator Stoica_TudorStoica Tudor Stoica_Tudor Data 23 aprilie 2018 17:49:06
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.76 kb
#include <fstream>
#include <vector>
#include <queue>
#define oo (1<<30)
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
const int NMax = 50005;
struct cel
{
    int val;
    bool incoada;
};
cel alah[NMax];
struct compara
{
    bool operator()(int x, int y)
    {
        return alah[x].val > alah[y].val;
    }
};
int n,m;
vector < pair<int,int> > v[NMax];
priority_queue<int, vector<int>, compara> coada;

void citire()
{
    fin>>n>>m;
    int a,b,c;
    for(int i=1; i<=m; i++)
    {
        fin>>a>>b>>c;
        v[a].push_back(make_pair(b,c));
    }

    for(int i=2; i<=n; i++)
    {
        alah[i].val=oo;
    }




}

void dijsktra(int nod_curent)
{
    alah[nod_curent].val=0;
    coada.push(nod_curent);
    alah[nod_curent].incoada=true;

    while(!coada.empty())
    {
        int operam=coada.top();
        coada.pop();
        alah[operam].incoada=false;

        for(size_t i=0; i<v[operam].size(); i++)
        {

            int vecin=v[operam][i].first;
            int cost=v[operam][i].second;

            if(cost+alah[operam].val<alah[vecin].val)
            {
                alah[vecin].val=cost+alah[operam].val;

                if(alah[vecin].incoada==false)
                {
                    alah[vecin].incoada=true;
                    coada.push(vecin);
                }
            }


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

    citire();
    dijsktra(1);
    afisare();
    return 0;
}

//5 7
//1 2 6
//1 4 1
//2 3 5
//2 5 2
//2 4 2
//3 5 5
//4 5 1