Stefan Müller
674553d29b
- Extract base graph logic from WeightedEdgeGraph into new Graph class - Add LabelGraph to replace old Graph class used by LanParty solver - Rename WeightedEdgeGraph to WeightGraph and change it to use new Graph class - Update affected solvers to use new graph classes
86 lines
2.4 KiB
C++
86 lines
2.4 KiB
C++
// Solutions to the Advent Of Code 2024.
|
|
// Copyright (C) 2025 Stefan Müller
|
|
//
|
|
// This program is free software: you can redistribute it and/or modify it under
|
|
// the terms of the GNU General Public License as published by the Free Software
|
|
// Foundation, either version 3 of the License, or (at your option) any later
|
|
// version.
|
|
//
|
|
// This program is distributed in the hope that it will be useful, but WITHOUT
|
|
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
// FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License along with
|
|
// this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
#include <aoc/common/WeightGraph.hpp>
|
|
|
|
#include <limits>
|
|
#include <queue>
|
|
|
|
constexpr int WeightGraph::getInfiniteDistance()
|
|
{
|
|
return std::numeric_limits<int>::max();
|
|
}
|
|
|
|
int WeightGraph::addVertex(const int weight)
|
|
{
|
|
vertexWeights_.push_back(weight);
|
|
return graph_.addVertex();
|
|
}
|
|
|
|
void WeightGraph::addEdge(const int vertex1, const int vertex2, const int weight)
|
|
{
|
|
edgeWeights_.push_back(weight);
|
|
graph_.addEdge(vertex1, vertex2);
|
|
}
|
|
|
|
int WeightGraph::getVertexWeight(const int vertex) const
|
|
{
|
|
return vertexWeights_[vertex];
|
|
}
|
|
|
|
int WeightGraph::getEdgeWeight(const int edge) const
|
|
{
|
|
return edgeWeights_[edge];
|
|
}
|
|
|
|
GraphPathsResult WeightGraph::dijkstra(const int source) const
|
|
{
|
|
GraphPathsResult result(graph_.getNVertices(), getInfiniteDistance(), -1);
|
|
auto compare = [&result](int left, int right) { return result.distances[left] > result.distances[right]; };
|
|
std::priority_queue<int, std::vector<int>, decltype(compare)> queue{ compare };
|
|
|
|
result.distances[source] = 0;
|
|
queue.push(source);
|
|
|
|
while (!queue.empty())
|
|
{
|
|
int v{ queue.top() };
|
|
queue.pop();
|
|
|
|
for (auto neighbor = begin(v); neighbor != end(); ++neighbor)
|
|
{
|
|
int newDistance{ result.distances[v] + edgeWeights_[neighbor->edge] };
|
|
if (result.distances[neighbor->vertex] > newDistance)
|
|
{
|
|
result.distances[neighbor->vertex] = newDistance;
|
|
result.predecessors[neighbor->vertex] = v;
|
|
queue.push(neighbor->vertex);
|
|
}
|
|
}
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
Graph::NeighborIterator WeightGraph::begin(const int vertex) const
|
|
{
|
|
return graph_.begin(vertex);
|
|
}
|
|
|
|
Graph::NeighborIterator WeightGraph::end() const
|
|
{
|
|
return graph_.end();
|
|
}
|