/// <summary>
/// Evaluates the similarity between two maps using the graph sampling evaluation of biagioni and eriksson.
/// Parameters are hardcoded, based on the ones we used in the corresponding research.
/// </summary>
/// <param name="GT">The ground truth map</param>
/// <param name="CT">the constructed map.</param>
/// <param name="amount">the amount of neighbourhood evaluations we average over</param>
/// <returns>A precision and recall value indicating the similarity between the maps.</returns>
public (float, float) EvalMap(Map GT, Map CT, int amount)
{
float precision = 0;
float recall = 0;
for (int k = 0; k < amount; k++)
{
Coordinate originGT = rand.GetRandomPointOnRoad(rand.GetWeightedRandomRoad(GT));
Coordinate originCT = CT.GetClosestPoint(originGT.location);
/* An extra step that is sometimes used in the literature when ground truth map is not pruned.
* while (Vector3.Distance(originCT.location, originGT.location) > 50)
* {
* originGT = rand.GetRandomCoordinate(rand.GetWeightedRandomRoad(GT));
* originCT = CT.GetClosestPoint(originGT.location);
* }
*/
List <Vector3> pointsGT = sampleNeighbourhood.GetNeighbourhood(GT, originGT, 500, 30);
List <Vector3> pointsCT = sampleNeighbourhood.GetNeighbourhood(CT, originCT, 500, 30);
MaxFlow flow = new MaxFlow(pointsGT.Count + pointsCT.Count + 2);
for (int i = 0; i < pointsCT.Count; i++)
{
flow.AddEdge(0, i + 1, 1);
}
for (int i = 0; i < pointsCT.Count; i++)
{
Vector3 pointCT = pointsCT[i];
for (int j = 0; j < pointsGT.Count; j++)
{
Vector3 pointGT = pointsGT[j];
if (Vector3.Distance(pointCT, pointGT) < 20)
{
flow.AddEdge(i + 1, j + pointsCT.Count + 1, 1);
}
}
}
for (int i = 0; i < pointsGT.Count; i++)
{
flow.AddEdge(i + pointsCT.Count + 1, 1 + pointsCT.Count + pointsGT.Count, 1);
}
float matching = flow.FindMaximumFlow(0, 1 + pointsCT.Count + pointsGT.Count).Item1;
precision += pointsCT.Count > 0 ? matching / pointsCT.Count : 0;
recall += pointsGT.Count > 0 ? matching / pointsGT.Count : 0;
}
return(precision / amount, recall / amount);
}
/// <summary>
/// Visualizes and evaluates a single random neighbourhood.
/// </summary>
/// <param name="GT">Ground truth map</param>
/// <param name="CT">contructed map</param>
/// <param name="originDistanceCondition"></param>
/// <param name="matchDistance"></param>
/// <returns></returns>
public (float, float) EvalNeighbourhood(Map GT, Map CT)
{
Coordinate originGT = rand.GetRandomPointOnRoad(rand.GetWeightedRandomRoad(GT));
Coordinate originCT = CT.GetClosestPoint(originGT.location);
/* An extra step that is sometimes used in the literature when ground truth map is not pruned.
* while (Vector3.Distance(originCT.location, originGT.location) > 50)
* {
* originGT = rand.GetRandomCoordinate(rand.GetWeightedRandomRoad(GT));
* originCT = CT.GetClosestPoint(originGT.location);
* }
*/
List <Vector3> pointsGT = sampleNeighbourhood.GetNeighbourhood(GT, originGT, 150, 30);
List <Vector3> pointsCT = sampleNeighbourhood.GetNeighbourhood(CT, originCT, 150, 30);
MaxFlow flow = new MaxFlow(pointsGT.Count + pointsCT.Count + 2);
for (int i = 0; i < pointsCT.Count; i++)
{
flow.AddEdge(0, i + 1, 1); // source edges
}
for (int i = 0; i < pointsCT.Count; i++) // edges between CT and GT
{
Vector3 pointCT = pointsCT[i];
for (int j = 0; j < pointsGT.Count; j++)
{
Vector3 pointGT = pointsGT[j];
if (Vector3.Distance(pointCT, pointGT) < 20)
{
flow.AddEdge(i + 1, j + pointsCT.Count + 1, 1);
}
}
}
for (int i = 0; i < pointsGT.Count; i++)
{
flow.AddEdge(i + pointsCT.Count + 1, 1 + pointsCT.Count + pointsGT.Count, 1); // sink edges
}
float matching;
int[,] graph;
(matching, graph) = flow.FindMaximumFlow(0, 1 + pointsCT.Count + pointsGT.Count);
float prec = pointsCT.Count > 0 ? matching / pointsCT.Count : 0;
float recall = pointsGT.Count > 0 ? matching / pointsGT.Count : 0;
return(prec, recall);
}
// このコードはテンプレートとして使えます。
// 0 <= v1 < n1, 0 <= v2 < n2
public static int[][] BipartiteMatching(int n1, int n2, int[][] des)
{
var sv = n1 + n2;
var ev = sv + 1;
var mf = new MaxFlow(ev + 1);
for (int i = 0; i < n1; ++i)
{
mf.AddEdge(sv, i, 1);
}
for (int j = 0; j < n2; ++j)
{
mf.AddEdge(n1 + j, ev, 1);
}
foreach (var e in des)
{
mf.AddEdge(e[0], n1 + e[1], 1);
}
mf.Dinic(sv, ev);
var map = mf.Map;
var r = new List <int[]>();
foreach (var se in map[sv])
{
if (se.Capacity > 0)
{
continue;
}
foreach (var e in map[se.To])
{
if (e.Capacity == 0)
{
r.Add(new[] { se.To, e.To - n1 });
break;
}
}
}
return(r.ToArray());
}
static object Solve()
{
var(h, w, n) = Read3();
var ps = Array.ConvertAll(new bool[n], _ => Read4());
var sv = 400;
var ev = sv + 1;
var mf = new MaxFlow(ev + 1);
for (int i = 0; i < h; i++)
{
mf.AddEdge(sv, i, 1);
}
for (int i = 0; i < w; i++)
{
mf.AddEdge(300 + i, ev, 1);
}
for (int i = 0; i < n; i++)
{
var(a, b, c, d) = ps[i];
var ri = 100 + i;
var ci = 200 + i;
mf.AddEdge(ri, ci, 1);
for (int j = a - 1; j < c; j++)
{
mf.AddEdge(j, ri, 1);
}
for (int j = b - 1; j < d; j++)
{
mf.AddEdge(ci, 300 + j, 1);
}
}
return(mf.Dinic(sv, ev));
}
static void Main()
{
var(n, m) = Read2();
var s = Array.ConvertAll(new bool[n], _ => Console.ReadLine().ToCharArray());
var sv = n * m;
var ev = sv + 1;
var mf = new MaxFlow(ev + 1);
var vs0 = new List <int>();
var vs1 = new HashSet <int>();
// checker board
for (int i = 0; i < n; i++)
{
for (int j = 0; j < m; j++)
{
if (s[i][j] == '#')
{
continue;
}
var v = m * i + j;
if ((i + j) % 2 == 0)
{
mf.AddEdge(sv, v, 1);
vs0.Add(v);
}
else
{
mf.AddEdge(v, ev, 1);
vs1.Add(v);
}
}
}
foreach (var v in vs0)
{
if (vs1.Contains(v - m))
{
mf.AddEdge(v, v - m, 1);
}
if (vs1.Contains(v + m))
{
mf.AddEdge(v, v + m, 1);
}
if (v % m != 0 && vs1.Contains(v - 1))
{
mf.AddEdge(v, v - 1, 1);
}
if (v % m != m - 1 && vs1.Contains(v + 1))
{
mf.AddEdge(v, v + 1, 1);
}
}
var M = mf.Dinic(sv, ev);
var map = mf.Map;
for (int i = 0; i < n; i++)
{
for (int j = 0; j < m; j++)
{
if (s[i][j] == '#')
{
continue;
}
var v = m * i + j;
if ((i + j) % 2 == 0)
{
var v2 = map[v].FirstOrDefault(e => e.Capacity == 0 && e.To != sv)?.To;
if (v2 == null)
{
continue;
}
var(i2, j2) = ((int)v2 / m, (int)v2 % m);
if (i == i2)
{
s[i][Math.Min(j, j2)] = '>';
s[i][Math.Max(j, j2)] = '<';
}
else
{
s[Math.Min(i, i2)][j] = 'v';
s[Math.Max(i, i2)][j] = '^';
}
}
}
}
Console.WriteLine(M);
foreach (var r in s)
{
Console.WriteLine(new string(r));
}
}
