From 5e6e456e5a8e5d86758fccc44d80035f1362f9e2 Mon Sep 17 00:00:00 2001
From: Arnaud Becheler <8360330+Becheler@users.noreply.github.com>
Date: Sun, 1 Nov 2026 01:17:15 +0100
Subject: [PATCH 1/2] bug: tiernan_all_cycles rejects adjacency_list

---
 test/tiernan_all_cycles.cpp | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/test/tiernan_all_cycles.cpp b/test/tiernan_all_cycles.cpp
index 3abe0d84f..92ec85f69 100644
--- a/test/tiernan_all_cycles.cpp
+++ b/test/tiernan_all_cycles.cpp
@@ -7,6 +7,7 @@
 #include <iostream>
 
 #include <boost/graph/graph_utility.hpp>
+#include <boost/graph/adjacency_list.hpp>
 #include <boost/graph/undirected_graph.hpp>
 #include <boost/graph/directed_graph.hpp>
 #include <boost/graph/tiernan_all_cycles.hpp>
@@ -103,6 +104,24 @@ void test_stateful_visitor_with_ref()
     BOOST_TEST_EQ(copied.count, static_cast< std::size_t >(0));
 }
 
+// adjacency_list has a vertex index but no renumber_vertex_indices, see issue 182
+void test_adjacency_list()
+{
+    using graph_t = boost::adjacency_list< boost::vecS, boost::vecS, boost::directedS >;
+    graph_t g(4);
+
+    // a triangle and a two cycle, so two elementary cycles
+    boost::add_edge(0, 1, g);
+    boost::add_edge(1, 2, g);
+    boost::add_edge(2, 0, g);
+    boost::add_edge(1, 3, g);
+    boost::add_edge(3, 1, g);
+
+    cycle_tally tally;
+    boost::tiernan_all_cycles(g, std::ref(tally));
+    BOOST_TEST_EQ(tally.count, static_cast< std::size_t >(2));
+}
+
 int main(int, char*[])
 {
     typedef undirected_graph<> Graph;
@@ -115,6 +134,7 @@ int main(int, char*[])
     test< DiGraph >();
 
     test_stateful_visitor_with_ref();
+    test_adjacency_list();
 
     return boost::report_errors();
 }

From 7844c670ac0462cdf72ff80f7b396f7b2ca8edda Mon Sep 17 00:00:00 2001
From: Arnaud Becheler <8360330+Becheler@users.noreply.github.com>
Date: Sun, 1 Nov 2026 01:18:14 +0100
Subject: [PATCH 2/2] fix: tiernan_all_cycles requires only a vertex_index map

---
 include/boost/graph/tiernan_all_cycles.hpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/boost/graph/tiernan_all_cycles.hpp b/include/boost/graph/tiernan_all_cycles.hpp
index 792681b93..aab2d7edd 100644
--- a/include/boost/graph/tiernan_all_cycles.hpp
+++ b/include/boost/graph/tiernan_all_cycles.hpp
@@ -150,8 +150,9 @@ namespace detail
         const ClosedMatrix& m)
     {
         BOOST_CONCEPT_ASSERT((IncidenceGraphConcept< Graph >));
-        BOOST_CONCEPT_ASSERT((VertexIndexGraphConcept< Graph >));
         typedef typename graph_traits< Graph >::vertex_descriptor Vertex;
+        using IndexMap = typename ::boost::property_map< Graph, ::boost::vertex_index_t >::const_type;
+        BOOST_CONCEPT_ASSERT((::boost::ReadablePropertyMapConcept< IndexMap, Vertex >));
 
         // get the vertices in question
         Vertex u = source(e, g), v = target(e, g);