Cod sursa(job #1379486)

Utilizator pulseOvidiu Giorgi pulse Data 6 martie 2015 18:05:22
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.18 kb
#include <bits/stdc++.h>
using namespace std;

const int MAXN = 50010;
const int INF = 0x3f3f3f3f;

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

int n, m, d[MAXN];
vector < pair <int, int> > g[MAXN];
queue <int> q;
bool inq[MAXN];

void bellman()
{
    for (int i = 2; i <= n; ++i)
        d[i] = INF;
    d[1] = 0;
    q.push(1);
    inq[1] = 1;
    while (!q.empty())
    {
        int node = q.front();
        q.pop();
        inq[node] = 0;
        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] > d[node] + c)
            {
                d[v] = d[node] + c;
                if (!inq[v])
                {
                    q.push(v);
                    inq[v] = 1;
                }
            }
        }
    }
    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));
    }
    bellman();
    return 0;
}