Cod sursa(job #2036952)

Utilizator LauraNaduLaura Nadu LauraNadu Data 11 octombrie 2017 15:05:22
Problema Algoritmul lui Dijkstra Scor 80
Compilator cpp Status done
Runda Arhiva educationala Marime 1.31 kb
#include<fstream>
#include<vector>
#include<queue>
#define inf 2147483648
using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
int n, m, nod, i, vecin, cost, costv;
long long d[50003];
class comparare
{
public:
    bool operator() (pair<int, int> a, pair<int, int> b)
    {
        return a.second<b.second;
    }
};
vector <pair <int, int> > l[250003];
priority_queue< pair<int, int>, vector<pair<int, int> >, comparare> heap;
int main()
{
    f>>n>>m;
    for(i=1;i<=m;i++)
    {
        int x, y, c;
        f>>x>>y>>c;
        l[x].push_back(make_pair(y, c));
    }
    for(i=2;i<=n;i++)
        d[i]=inf;
    heap.push(make_pair(0, 1));
    while(!heap.empty())
    {
        nod=heap.top().second;
        cost=heap.top().first;
        heap.pop();
        if(d[nod]==cost)
            for(vector< pair<int, int> > :: iterator it=l[nod].begin(); it!=l[nod].end(); it++)
            {
                vecin=it->first;
                costv=it->second;
                if(d[vecin]>costv+cost)
                {
                    d[vecin]=costv+cost;
                    heap.push(make_pair(d[vecin], vecin));
                }
            }
    }
    for(i=2;i<=n;i++)
        if(d[i]!=inf)
            g<<d[i]<<" ";
        else g<<"0 ";
    return 0;
}