node parent( node_list& v, node n )
{
if( n >= v.size( ) ) {
for( unsigned i = v.size( ); i <= n; i++ ) {
v.push_back( i );
}
}
if( v[ n ] == n ) return n;
v[ n ] = parent( v, v[ n ] );
return v[ n ];
}
void Dijkstra(int start, const node_list &node_list,
vector<float> &min_distance,
vector<int> &previous)
{
int n = node_list.size();
min_distance.clear();
min_distance.resize(n, max_distance);
min_distance[start] = 0;
previous.clear();
previous.resize(n, -1);
set< pair<float, int> > vertex_queue;
vertex_queue.insert(make_pair(min_distance[start], start));
while (!vertex_queue.empty())
{
float dist = vertex_queue.begin()->first;
int u = vertex_queue.begin()->second;
vertex_queue.erase(vertex_queue.begin());
const vector<neighbor> &neighbors = node_list[u];
for (vector<neighbor>::const_iterator it
= neighbors.begin();
it != neighbors.end();
it++)
{
int v = it->next;
float distance = it->distance;
float distance_through_u = dist + distance;
if (distance_through_u < min_distance[v])
{
vertex_queue.erase(make_pair(min_distance[v], v));
min_distance[v] = distance_through_u;
previous[v] = u;
vertex_queue.insert(make_pair(min_distance[v], v));
}
}
}
}