Graph

2026-09-07 18:48:16 +08:00
parent 1564716731
commit c945aa211f
138 changed files with 10337 additions and 150 deletions
@@ -0,0 +1,66 @@
+#ifndef INCLUDED_C_DIJKSTRASP_H
+#define INCLUDED_C_DIJKSTRASP_H
+
+#ifndef INCLUDED_C_EDGEWEIGHTEDDIGRAPH_H
+#include <c_EdgeWeightedDigraph.h>
+#endif /*INCLUDED_C_EDGEWEIGHTEDDIGRAPH_H*/
+
+#ifndef INCLUDED_C_VERTEXIDLIST_H
+#include <c_VertexIdList.h>
+#endif /*INCLUDED_C_VERTEXIDLIST_H*/
+
+
+/* ------------------------------------------------------------------------------------------------------------------ */
+/*  */
+
+typedef struct {
+    c_size_t*          edge_to;       /* edge_to[w] = entering directed edge_id on shortest path to w */
+    c_size_t*          from_vertex;   /* from_vertex[w] = source vertex parent link on path to w */
+    double*            dist_to;       /* dist_to[w] = cumulative distance tracking matrix */
+    c_size_t           s;             /* The starting source vertex index */
+    c_size_t           V;             /* Total number of vertices in the digraph */
+    c_Allocator_t      allocator;     /* Deep copy of the user-provided allocator */
+} c_DijkstraSP_t;
+
+/* ------------------------------------------------------------------------------------------------------------------ */
+/*  */
+
+/**
+ * @brief Computes a shortest-paths tree from the source vertex 's' in the edge-weighted digraph.
+ * @param allocator Explicit allocator context used to configure internal tracking state memory
+ */
+c_err_t c_DijkstraSP_Init(c_DijkstraSP_t* self, c_EdgeWeightedDigraph_t* graph, c_size_t s, c_Allocator_t* allocator);
+
+/**
+ * @brief Releases internal tracking buffers safely.
+ */
+void c_DijkstraSP_Destroy(c_DijkstraSP_t* self);
+
+/**
+ * @brief Is there a directed path from the source vertex 's' to vertex 'v'?
+ */
+C_STATIC_FORCE_INLINE
+c_bool_t c_DijkstraSP_HasPathTo(c_DijkstraSP_t* self, c_size_t v) {
+    if (!self || v >= self->V || !self->dist_to) return C_FALSE;
+    return self->dist_to[v] < DBL_MAX;
+}
+
+/**
+ * @brief Returns the distance of the shortest path from the source vertex 's' to vertex 'v'.
+ * @return Distance value, or DBL_MAX if unreachable / parameter error
+ */
+C_STATIC_FORCE_INLINE
+double c_DijkstraSP_DistTo(c_DijkstraSP_t* self, c_size_t v) {
+    if (!self || v >= self->V || !self->dist_to) return DBL_MAX;
+    return self->dist_to[v];
+}
+
+/**
+ * @brief Reconstructs the exact shortest path from the source vertex 's' to vertex 'v' and appends it to out_path.
+ * @param out_path An initialized c_VertexIdList_t container to collect the sequence of global directed edge_ids.
+ */
+c_err_t c_DijkstraSP_PathTo(c_DijkstraSP_t* self, c_size_t v, c_VertexIdList_t* out_path);
+
+
+
+#endif /*INCLUDED_C_DIJKSTRASP_H*/