From be827b3536914906a57ef5b3a7489dce7ad0c9eb Mon Sep 17 00:00:00 2001
From: Tobias Kempf <kempf.tobias@web.de>
Date: Wed, 20 Nov 2024 22:53:49 +0100
Subject: [PATCH] Fix add/remove edges/pins

---
 mt-kahypar/datastructures/static_hypergraph.h | 49 +++++--------------
 mt-kahypar/dynamic/dynamic_io.h               |  6 +--
 2 files changed, 14 insertions(+), 41 deletions(-)

diff --git a/mt-kahypar/datastructures/static_hypergraph.h b/mt-kahypar/datastructures/static_hypergraph.h
index 5506883dc..cbf1426fa 100644
--- a/mt-kahypar/datastructures/static_hypergraph.h
+++ b/mt-kahypar/datastructures/static_hypergraph.h
@@ -772,38 +772,24 @@ class StaticHypergraph {
   // ####################### Remove / Restore Pins #######################
 
   /*!
-   * Removes a pin from the hyperedge.
+   * Removes a pin.
    */
-  void removeIncidentPinFromEdge(const HyperedgeID hn, const HypernodeID he) {
+  void removePin(const HyperedgeID hn, const HypernodeID he) {
     using std::swap;
     ASSERT(edgeIsEnabled(he), "Hyperedge" << he << "is disabled");
     ASSERT(nodeIsEnabled(hn), "Hypernode" << hn << "is disabled");
-    const size_t pos = hyperedge(he).firstEntry();
-    const size_t end = hyperedge(he).firstInvalidEntry();
-    for ( size_t i = pos; i < end; ++i ) {
-      if ( _incidence_array[i] == hn ) {
-        swap(_incidence_array[i], _incidence_array[end - 1]);
-        hyperedge(he).setSize(hyperedge(he).size() - 1);
-        return;
-      }
-    }
+    removeIncidentEdgeFromHypernode(he, hn);
+    removeIncidentHypernodeFromEdge(hn, he);
   }
 
   /*!
-   * Restores a pin previously removed from the hyperedge.
+   * Restores a pin previously removed
    */
-  void restoreIncidentPinToEdge(const HyperedgeID hn, const HypernodeID he) {
+  void restorePin(const HyperedgeID hn, const HypernodeID he) {
     ASSERT(edgeIsEnabled(he), "Hyperedge" << he << "is disabled");
     ASSERT(nodeIsEnabled(hn), "Hypernode" << hn << "is disabled");
-    const size_t pos = hyperedge(he).firstEntry();
-    const size_t end = hyperedge(he).firstInvalidEntry();
-    for ( size_t i = pos; i < end; ++i ) {
-      if ( _incidence_array[i] == hn ) {
-        return;
-      }
-    }
-    _incidence_array[end] = hn;
-    hyperedge(he).setSize(hyperedge(he).size() + 1);
+    insertIncidentEdgeToHypernode(he, hn);
+    restoreIncidentHypernodeToEdge(hn, he);
   }
 
   // ####################### Remove / Restore Hyperedges #######################
@@ -824,18 +810,6 @@ class StaticHypergraph {
     disableHyperedge(he);
   }
 
-  /*!
-   * Removes a hyperedge from the hypergraph without removing the pins.
-   *
-   * NOTE, this function is not thread-safe and should only be called in a single-threaded
-   * setting.
-   */
-  void removeEdgeWithoutRemovingPins(const HyperedgeID he) {
-    ASSERT(edgeIsEnabled(he), "Hyperedge" << he << "is disabled");
-    ++_num_removed_hyperedges;
-    disableHyperedge(he);
-  }
-
   /*!
    * Restores a hyperedge previously removed from the hypergraph.
    * This includes the restoration of he to all of its pins.
@@ -846,10 +820,9 @@ class StaticHypergraph {
   void restoreEdge(const HyperedgeID he) {
     ASSERT(!edgeIsEnabled(he), "Hyperedge" << he << "is enabled");
     enableHyperedge(he);
-    //TODO only needed if edge was removed
-//    for ( const HypernodeID& pin : pins(he) ) {
-//      insertIncidentEdgeToHypernode(he, pin);
-//    }
+    for ( const HypernodeID& pin : pins(he) ) {
+      insertIncidentEdgeToHypernode(he, pin);
+    }
     --_num_removed_hyperedges;
   }
 
diff --git a/mt-kahypar/dynamic/dynamic_io.h b/mt-kahypar/dynamic/dynamic_io.h
index 612bf5eaa..6c2e1febc 100644
--- a/mt-kahypar/dynamic/dynamic_io.h
+++ b/mt-kahypar/dynamic/dynamic_io.h
@@ -54,7 +54,7 @@ namespace mt_kahypar::dyn {
 
       // Disable all the edges using seed
       for ( const HyperedgeID& he : disabling_order ) {
-        hypergraph_s.removeEdgeWithoutRemovingPins(he);
+        hypergraph_s.removeEdge(he);
         added_edges.push_back(he);
       }
 
@@ -90,14 +90,14 @@ namespace mt_kahypar::dyn {
           if ( !hypergraph_s.nodeIsEnabled(hn) ) {
             continue;
           }
-          hypergraph_s.removeIncidentPinFromEdge(hn, he);
+          hypergraph_s.removePin(hn, he);
           added_pins.push_back({hn, he});
         }
       }
 
       // re-enable all pins until start_id
       for ( auto [hn, he]: added_pins ) {
-        hypergraph_s.restoreIncidentPinToEdge(hn, he);
+        hypergraph_s.restorePin(hn, he);
         ASSERT(std::find(hypergraph_s.pins(he).begin(), hypergraph_s.pins(he).end(), hn) != hypergraph_s.pins(he).end());
       }