Cod sursa(job #1413791)

Utilizator pulseOvidiu Giorgi pulse Data 2 aprilie 2015 08:53:33
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.15 kb
#include <fstream>
#include <vector>
#include <set>

using namespace std;

const int maxn = 50010;
const int inf = 2e9;

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

int n, m, d[maxn];
vector <pair <int, int> > g[maxn];
set <pair <int, int> > s;

void dijkstra()
{
    for (int i = 2; i <= n; i++)
        d[i] = inf;
    s.insert(make_pair(0, 1));
    while (!s.empty())
    {
        int cn = s.begin() -> first;
        int node = s.begin() -> second;
        s.erase(s.begin());
        for (vector <pair <int, int> > :: iterator it = g[node].begin(); it != g[node].end(); ++it)
        {
            int v = it -> first;
            int c = it -> second;
            if (d[v] > cn + c)
            {
                d[v] = cn + c;
                s.insert(make_pair(d[v], v));
            }
        }
    }
    for (int i = 2; i <= n; i++)
    {
        if (d[i] != inf) fout << d[i] << " ";
        else fout << "0 ";
    }
}

int main()
{
    fin >> n >> m;
    for (int a, b, c; m; --m)
    {
        fin >> a >> b >> c;
        g[a].push_back(make_pair(b, c));
    }
    dijkstra();
    return 0;
}