Graph

2026-09-07 18:48:16 +08:00
parent 1564716731
commit c945aa211f
138 changed files with 10337 additions and 150 deletions
@@ -0,0 +1,67 @@
+#ifndef INCLUDED_C_NONRECURSIVEGABOWSCC_H
+#define INCLUDED_C_NONRECURSIVEGABOWSCC_H
+
+#ifndef INCLUDED_C_DIGRAPH_H
+#include <c_Digraph.h>
+#endif /*INCLUDED_C_DIGRAPH_H*/
+
+
+/* ------------------------------------------------------------------------------------------------------------------ */
+/*  */
+
+typedef struct {
+    c_bool_t*          marked;       /* Visited tracking array (size of graph->V) */
+    c_size_t*          id;           /* id[v] = component identifier containing v (0 to count-1) */
+    c_size_t*          pre;          /* pre[v] = preorder index of vertex v */
+    c_size_t*          scc_stack;    /* Stack to keep track of vertices in the current SCC candidate */
+    c_size_t           scc_stack_sz; /* Size of scc_stack */
+    c_size_t*          path_stack;   /* Stack to determine root of strongly connected components */
+    c_size_t           path_stack_sz;/* Size of path_stack */
+    c_size_t           pre_counter;  /* Preorder index sequencing counter */
+    c_size_t           count;        /* Total number of strongly connected components discovered */
+    c_size_t           V;            /* Stored vertex count for safe boundary check lookups */
+    c_Allocator_t      allocator;    /* Deep copy of the user-provided allocator */
+} c_NonrecursiveGabowSCC_t;
+
+/* ------------------------------------------------------------------------------------------------------------------ */
+/*  */
+
+/**
+ * @brief Non-recursively computes strongly connected components for the specified digraph using Gabow's algorithm.
+ * @param allocator Explicit allocator context used to allocate internal routing arrays
+ */
+c_err_t c_NonrecursiveGabowSCC_Init(c_NonrecursiveGabowSCC_t* self, c_Digraph_t* graph, c_Allocator_t* allocator);
+
+/**
+ * @brief Releases internal tracking buffers
+ */
+void c_NonrecursiveGabowSCC_Destroy(c_NonrecursiveGabowSCC_t* self);
+
+/**
+ * @brief Are vertices 'v' and 'w' strongly connected (belong to the same SCC)?
+ */
+C_STATIC_FORCE_INLINE
+c_bool_t c_NonrecursiveGabowSCC_StronglyConnected(c_NonrecursiveGabowSCC_t* self, c_size_t v, c_size_t w) {
+    if (!self || !self->id || v >= self->V || w >= self->V) return C_FALSE;
+    return self->id[v] == self->id[w];
+}
+
+/**
+ * @brief Returns the component id containing vertex 'v'
+ * @return Component integer ID (0 to count-1), or C_SIZE_MAX on boundary check failures
+ */
+C_STATIC_FORCE_INLINE
+c_size_t c_NonrecursiveGabowSCC_GetId(const c_NonrecursiveGabowSCC_t* self, c_size_t v) {
+    if (!self || !self->id || v >= self->V) return C_SIZE_MAX;
+    return self->id[v];
+}
+
+/**
+ * @brief Returns the total number of strongly connected components
+ */
+C_STATIC_FORCE_INLINE
+c_size_t c_NonrecursiveGabowSCC_GetCount(const c_NonrecursiveGabowSCC_t* self) {
+    return self ? self->count : 0;
+}
+
+#endif /*INCLUDED_C_NONRECURSIVEGABOWSCC_H*/