From c162b92e8ca9c2b2b9b8af1b0a96ffaa3f8d9de3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maximilian=20Ke=C3=9Fler?= <git@maximilian-kessler.de>
Date: Sat, 4 Nov 2023 19:49:54 +0100
Subject: [PATCH] initialize with greedy matching

---
 edmonds.cpp | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/edmonds.cpp b/edmonds.cpp
index d69f9f9..d0bb86e 100644
--- a/edmonds.cpp
+++ b/edmonds.cpp
@@ -121,8 +121,26 @@ Graph maximum_matching_from_initial_matching(Graph & graph)
    }
 };
 
-Graph maximum_matching(Graph & graph) {
+void find_greedy_matching(Graph & graph)
+{
    graph.reset_matching();
+   for(NodeId node_id = 0; node_id < graph.num_nodes(); ++node_id)
+   {
+      if (graph.matched_neighbor(node_id) == node_id) {
+         for(NodeId neighbor_id : graph.node(node_id).neighbors())
+         {
+            if(graph.matched_neighbor(neighbor_id) == neighbor_id)
+            {
+               graph.node(neighbor_id).matched_neighbor = node_id;
+               graph.node(node_id).matched_neighbor = neighbor_id;
+            }
+         }
+      }
+   }
+}
+
+Graph maximum_matching(Graph & graph) {
+   find_greedy_matching(graph);
    return maximum_matching_from_initial_matching(graph);
 }