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turbonss/cxxmph/trigraph.cc

82 lines
2.4 KiB
C++

#include <cassert>
#include <limits>
#include <iostream>
#include "trigraph.h"
using std::cerr;
using std::endl;
using std::vector;
namespace {
static const uint32_t kInvalidEdge = std::numeric_limits<uint32_t>::max();
}
namespace cxxmph {
TriGraph::TriGraph(uint32_t nvertices, uint32_t nedges)
: nedges_(0),
edges_(nedges),
next_edge_(nedges),
first_edge_(nvertices, kInvalidEdge),
vertex_degree_(nvertices, 0) { }
void TriGraph::ExtractEdgesAndClear(vector<Edge>* edges) {
vector<Edge>().swap(next_edge_);
vector<uint32_t>().swap(first_edge_);
vector<uint8_t>().swap(vertex_degree_);
nedges_ = 0;
edges->swap(edges_);
}
void TriGraph::AddEdge(const Edge& edge) {
edges_[nedges_] = edge;
assert(first_edge_.size() > edge[0]);
assert(first_edge_.size() > edge[1]);
assert(first_edge_.size() > edge[0]);
assert(first_edge_.size() > edge[1]);
assert(first_edge_.size() > edge[2]);
assert(next_edge_.size() > nedges_);
next_edge_[nedges_] = Edge(
first_edge_[edge[0]], first_edge_[edge[1]], first_edge_[edge[2]]);
first_edge_[edge[0]] = first_edge_[edge[1]] = first_edge_[edge[2]] = nedges_;
++vertex_degree_[edge[0]];
++vertex_degree_[edge[1]];
++vertex_degree_[edge[2]];
++nedges_;
}
void TriGraph::RemoveEdge(uint32_t current_edge) {
// cerr << "Removing edge " << current_edge << " from " << nedges_ << " existing edges " << endl;
for (int i = 0; i < 3; ++i) {
uint32_t vertex = edges_[current_edge][i];
uint32_t edge1 = first_edge_[vertex];
uint32_t edge2 = kInvalidEdge;
uint32_t j = 0;
while (edge1 != current_edge && edge1 != kInvalidEdge) {
edge2 = edge1;
if (edges_[edge1][0] == vertex) j = 0;
else if (edges_[edge1][1] == vertex) j = 1;
else j = 2;
edge1 = next_edge_[edge1][j];
}
assert(edge1 != kInvalidEdge);
if (edge2 != kInvalidEdge) next_edge_[edge2][j] = next_edge_[edge1][i];
else first_edge_[vertex] = next_edge_[edge1][i];
--vertex_degree_[vertex];
}
}
void TriGraph::DebugGraph() const {
int i;
for(i = 0; i < edges_.size(); i++){
cerr << i << " " << edges_[i][0] << " " << edges_[i][1] << " " << edges_[i][2]
<< " nexts " << next_edge_[i][0] << " " << next_edge_[i][1] << " " << next_edge_[i][2] << endl;
}
for(i = 0; i < first_edge_.size();i++){
cerr << "first for vertice " <<i << " " << first_edge_[i] << endl;
}
}
} // namespace cxxmph