Graph

Graph/c_DijkstraAllPairsSP.c

@@ -0,0 +1,58 @@
+#include <c_DijkstraAllPairsSP.h>
+
+c_err_t c_DijkstraAllPairsSP_Init(c_DijkstraAllPairsSP_t* self, c_EdgeWeightedDigraph_t* graph, c_Allocator_t* allocator) {
+    if (!self || !graph) return C_ERR_PARAM;
+
+    self->allocator = allocator ? *allocator : c_DefaultAllocator;
+    self->V = graph->V;
+    self->sp_matrix = NULL;
+
+    if (self->V == 0) return C_SUCCESS;
+
+    /* 1. Allocate an array of DijkstraSP structures */
+    self->sp_matrix = (c_DijkstraSP_t*)c_Allocator_Calloc(
+        &self->allocator,
+        self->V,
+        sizeof(c_DijkstraSP_t)
+    );
+    if (!self->sp_matrix) return C_ERR_NOMEM;
+
+    /* 2. Run a full single-source Dijkstra search engine out from each vertex */
+    for (c_size_t v = 0; v < self->V; ++v) {
+        c_err_t err = c_DijkstraSP_Init(&self->sp_matrix[v], graph, v, allocator);
+
+        if (err != C_SUCCESS) {
+            /* Atomic Rollback: Destroy previously allocated instances to prevent OOM memory leaks */
+            for (c_size_t i = 0; i < v; ++i) {
+                c_DijkstraSP_Destroy(&self->sp_matrix[i]);
+            }
+            c_Allocator_Free(&self->allocator, self->sp_matrix);
+            self->sp_matrix = NULL;
+            self->V = 0;
+            return err;
+        }
+    }
+
+    return C_SUCCESS;
+}
+
+void c_DijkstraAllPairsSP_Destroy(c_DijkstraAllPairsSP_t* self) {
+    if (!self) return;
+
+    if (self->sp_matrix) {
+        /* Safely deallocate every single active search instance */
+        for (c_size_t i = 0; i < self->V; ++i) {
+            c_DijkstraSP_Destroy(&self->sp_matrix[i]);
+        }
+        c_Allocator_Free(&self->allocator, self->sp_matrix);
+        self->sp_matrix = NULL;
+    }
+    self->V = 0;
+}
+
+c_err_t c_DijkstraAllPairsSP_Path(c_DijkstraAllPairsSP_t* self, c_size_t u, c_size_t v, c_VertexIdList_t* out_path) {
+    if (!self || !self->sp_matrix || u >= self->V || v >= self->V || !out_path) return C_ERR_PARAM;
+
+    /* Safely delegate extraction to the underlying single-source engine */
+    return c_DijkstraSP_PathTo(&self->sp_matrix[u], v, out_path);
+}