From b05b8410d3535b1bc045e21fc7685c259f4719c8 Mon Sep 17 00:00:00 2001
From: Richard Wong <richard@richardwong.io>
Date: Mon, 6 May 2024 16:32:01 +0900
Subject: [PATCH] Feat: added 3 approaches to get MPS: planarity test, exact
 via ILP, and cactus

---
 ...gdf_mps_simple.cpp => ogdf_mps_cactus.cpp} |  5 +-
 make_planar/ogdf_mps_exact.cpp                |  4 -
 make_planar/ogdf_mps_fast.cpp                 | 74 +++++++++++++++++++
 3 files changed, 77 insertions(+), 6 deletions(-)
 rename make_planar/{ogdf_mps_simple.cpp => ogdf_mps_cactus.cpp} (92%)
 create mode 100644 make_planar/ogdf_mps_fast.cpp

diff --git a/make_planar/ogdf_mps_simple.cpp b/make_planar/ogdf_mps_cactus.cpp
similarity index 92%
rename from make_planar/ogdf_mps_simple.cpp
rename to make_planar/ogdf_mps_cactus.cpp
index cfad9e4..ff35e5c 100644
--- a/make_planar/ogdf_mps_simple.cpp
+++ b/make_planar/ogdf_mps_cactus.cpp
@@ -1,9 +1,9 @@
 #include <ogdf/basic/STNumbering.h>
 #include <ogdf/fileformats/GraphIO.h>
 
-#include <ogdf/planarity/PlanarSubgraphFast.h>
 // #include <ogdf/planarity/PlanarSubgraphBoyerMyrvold.h>
 #include <ogdf/planarity/MaximumPlanarSubgraph.h>
+#include <ogdf/planarity/PlanarSubgraphCactus.h>
 #include <ogdf/planarity/MaximalPlanarSubgraphSimple.h>
 
 #include <iostream>
@@ -40,7 +40,8 @@ int main(int argc, char* argv[])
     std::cout << "start planarization" << std::endl;
     List<edge> *delEdges = new List<edge>; // empty list
 
-    ogdf::MaximalPlanarSubgraphSimple<int> mps(*(new PlanarSubgraphFast<int>));
+    PlanarSubgraphCactus<int> psc;
+    ogdf::MaximalPlanarSubgraphSimple<int> mps(psc);
     mps.call(G, *delEdges);
 
     
diff --git a/make_planar/ogdf_mps_exact.cpp b/make_planar/ogdf_mps_exact.cpp
index 5b72893..3c2ffed 100644
--- a/make_planar/ogdf_mps_exact.cpp
+++ b/make_planar/ogdf_mps_exact.cpp
@@ -27,10 +27,6 @@ int main(int argc, char* argv[])
         return 1;
     }
 
-        
-    NodeArray<int> numbering(G);
-    int num = computeSTNumbering(G, numbering, nullptr, nullptr, true);
-    OGDF_ASSERT(num == G.numberOfNodes());
 
     // print after input
     // graphPrinter(G);
diff --git a/make_planar/ogdf_mps_fast.cpp b/make_planar/ogdf_mps_fast.cpp
new file mode 100644
index 0000000..df5786d
--- /dev/null
+++ b/make_planar/ogdf_mps_fast.cpp
@@ -0,0 +1,74 @@
+/* 
+ * 
+ */
+#include <ogdf/basic/STNumbering.h>
+#include <ogdf/fileformats/GraphIO.h>
+
+#include <ogdf/planarity/PlanarSubgraphFast.h>
+// #include <ogdf/planarity/PlanarSubgraphBoyerMyrvold.h>
+#include <ogdf/planarity/MaximumPlanarSubgraph.h>
+#include <ogdf/planarity/MaximalPlanarSubgraphSimple.h>
+
+#include <iostream>
+
+using namespace ogdf;
+
+
+int main(int argc, char* argv[]) 
+{
+
+    string inputFile = argv[1];
+    Graph G;
+
+    if (!GraphIO::read(G, inputFile, GraphIO::readGML)) {
+        std::cerr << "Could not read input.gml" << std::endl;
+        return 1;
+    }
+
+        
+    NodeArray<int> numbering(G);
+    int num = computeSTNumbering(G, numbering, nullptr, nullptr, true);
+    OGDF_ASSERT(num == G.numberOfNodes());
+
+    // print after input
+    // graphPrinter(G);
+    std::cout << "G Planarity: " << ogdf::isPlanar(G) << std::endl;
+    std::cout << "Original number of nodes: " << G.numberOfNodes() << std::endl;
+    std::cout << "Original number of edges: " << G.numberOfEdges() << std::endl;
+
+    // separator for planarization
+    // <-------------->
+
+    // PQ implementation to make planar subgraph
+    std::cout << "start planarization" << std::endl;
+    List<edge> *delEdges = new List<edge>; // empty list
+
+    PlanarSubgraphFast<int> psf;
+    // comment out to use default options
+    // psf.runs(1); 
+    ogdf::MaximalPlanarSubgraphSimple<int> mps(psf);
+    mps.call(G, *delEdges);
+
+    
+    std::cout << "Edges removed:" << delEdges->size() << std::endl;
+
+
+    // delete removed edges
+    for (edge e: *delEdges) {
+        // print removed edges
+        // std::cout << e->adjSource() << std::endl;
+        G.delEdge(e);
+    }
+
+
+    // write processed graph to new gml file
+    // GraphIO::write(G, "output.gml", GraphIO::writeGML);
+    
+
+    std::cout << "G planarity: " << ogdf::isPlanar(G) << std::endl;
+    std::cout << "Original number of nodes: " << G.numberOfNodes() << std::endl;
+    std::cout << "Subgraph number of edges: " << G.numberOfEdges() << std::endl;
+
+
+    return 0;
+}