Introduce custom adjacency-list based graph

src/nfagraph/ng_is_equal.cpp

@@ -77,6 +77,26 @@ private:
     ReportID a_rep;
     ReportID b_rep;
 };
+
+/** Comparison functor used to sort by vertex_index. */
+template<typename Graph>
+struct VertexIndexOrdering {
+    explicit VertexIndexOrdering(const Graph &g_in) : g(g_in) {}
+    bool operator()(typename Graph::vertex_descriptor a,
+                    typename Graph::vertex_descriptor b) const {
+        assert(a == b || g[a].index != g[b].index);
+        return g[a].index < g[b].index;
+    }
+private:
+    const Graph &g;
+};
+
+template<typename Graph>
+static
+VertexIndexOrdering<Graph> make_index_ordering(const Graph &g) {
+    return VertexIndexOrdering<Graph>(g);
+}
+
 }
 
 static
@@ -109,7 +129,7 @@ bool is_equal_i(const NGHolder &a, const NGHolder &b,
     for (size_t i = 0; i < vert_a.size(); i++) {
         NFAVertex va = vert_a[i];
         NFAVertex vb = vert_b[i];
-        DEBUG_PRINTF("vertex %u\n", a[va].index);
+        DEBUG_PRINTF("vertex %zu\n", a[va].index);
 
         // Vertex index must be the same.
         if (a[va].index != b[vb].index) {