Graph

Graph/c_Cycle.h

@@ -0,0 +1,53 @@
+#ifndef INCLUDED_C_CYCLE_H
+#define INCLUDED_C_CYCLE_H
+
+#ifndef INCLUDED_C_GRAPH_H
+#include <c_Graph.h>
+#endif /*INCLUDED_C_GRAPH_H*/
+
+
+#ifndef INCLUDED_C_VERTEXIDLIST_H
+#include <c_VertexIdList.h>
+#endif /*INCLUDED_C_VERTEXIDLIST_H*/
+
+
+/* ------------------------------------------------------------------------------------------------------------------ */
+/*  */
+
+typedef struct {
+    c_bool_t*     marked;       // marked[v] = has vertex v been visited?
+    c_size_t*     edge_to;      // edge_to[v] = previous vertex on DFS path to v
+    c_VertexIdList_t cycle;       // Stores the path sequence of the detected cycle
+    c_bool_t      has_cycle;    // Global structural cycle status flag
+    c_size_t      V;      // Cached local vertex dimension boundary
+    c_Allocator_t allocator;    // Memory allocator copy
+} c_Cycle_t;
+
+/* ------------------------------------------------------------------------------------------------------------------ */
+/*  */
+
+/**
+ * @brief Computes whether the undirected graph contains a cycle.
+ * @param self Pointer to the uninitialized cycle tracking structure.
+ * @param G Pointer to the constant target graph object to verify.
+ * @param allocator Memory allocator instance pointer to deploy.
+ * @return C_SUCCESS on success, or an error status code on allocation failure.
+ */
+c_err_t  c_Cycle_Init(c_Cycle_t* self, const c_Graph_t* G, c_Allocator_t* allocator);
+
+/**
+ * @brief Drops all internal allocation states within the cycle instance safely.
+ */
+void     c_Cycle_Destroy(c_Cycle_t* self);
+
+/**
+ * @brief Does the graph contain at least one cycle?
+ */
+c_bool_t c_Cycle_HasCycle(const c_Cycle_t* self);
+
+/**
+ * @brief Returns the vertex sequence forming the cycle path, or empty if acyclic.
+ */
+const c_VertexIdList_t* c_Cycle_Path(const c_Cycle_t* self);
+
+#endif /*INCLUDED_C_CYCLE_H*/