Graph

2026-09-07 18:48:16 +08:00
parent 1564716731
commit c945aa211f
138 changed files with 10337 additions and 150 deletions
@@ -0,0 +1,63 @@
+#ifndef INCLUDED_C_BREADTHFIRSTDIRECTEDPATHS_H
+#define INCLUDED_C_BREADTHFIRSTDIRECTEDPATHS_H
+
+#ifndef INCLUDED_C_DIGRAPH_H
+#include <c_Digraph.h>
+#endif /*INCLUDED_C_DIGRAPH_H*/
+
+#ifndef INCLUDED_C_VERTEXIDLIST_H
+#include <c_VertexIdList.h>
+#endif /*INCLUDED_C_VERTEXIDLIST_H*/
+
+
+/* ------------------------------------------------------------------------------------------------------------------ */
+/*  */
+
+typedef struct {
+    c_bool_t*      marked;      /* Visited tracking array (size of graph->V) */
+    c_size_t*      edge_to;     /* edge_to[w] = last edge on shortest path from s to w */
+    c_size_t*      dist_to;     /* dist_to[w] = number of edges on shortest path from s to w */
+    c_size_t       s;           /* Source vertex */
+    c_Allocator_t  allocator;   /* Deep copy of the user-provided allocator */
+} c_BreadthFirstDirectedPaths_t;
+
+/* ------------------------------------------------------------------------------------------------------------------ */
+/*  */
+
+/**
+ * @brief Computes shortest directed paths from a single source vertex 's' using BFS
+ * @param allocator Explicit allocator context used to allocate internal routing arrays
+ */
+c_err_t c_BreadthFirstDirectedPaths_Init(c_BreadthFirstDirectedPaths_t* self, const c_Digraph_t* graph, c_size_t s, c_Allocator_t* allocator);
+
+/**
+ * @brief Releases internal tracking buffers
+ */
+void c_BreadthFirstDirectedPaths_Destroy(c_BreadthFirstDirectedPaths_t* self);
+
+/**
+ * @brief Is there a directed path from the source 's' to vertex 'v'?
+ */
+C_STATIC_FORCE_INLINE
+c_bool_t c_BreadthFirstDirectedPaths_HasPathTo(c_BreadthFirstDirectedPaths_t* self, c_size_t v, c_size_t total_V) {
+    if (!self || !self->marked || v >= total_V) return C_FALSE;
+    return self->marked[v];
+}
+
+/**
+ * @brief Returns the number of edges in a shortest path from the source 's' to vertex 'v'
+ * @return Distance value, or C_SIZE_MAX if unreachable / parameter error
+ */
+C_STATIC_FORCE_INLINE
+c_size_t c_BreadthFirstDirectedPaths_DistTo(c_BreadthFirstDirectedPaths_t* self, c_size_t v, c_size_t total_V) {
+    if (!self || v >= total_V || !self->marked[v]) return C_SIZE_MAX;
+    return self->dist_to[v];
+}
+
+/**
+ * @brief Reconstructs the exact shortest path from source 's' to vertex 'v' and appends it to out_path
+ */
+c_err_t c_BreadthFirstDirectedPaths_PathTo(c_BreadthFirstDirectedPaths_t* self, c_size_t v, c_size_t total_V, c_VertexIdList_t* out_path);
+
+
+#endif /*INCLUDED_C_BREADTHFIRSTDIRECTEDPATHS_H*/