67 lines
2.6 KiB
C
67 lines
2.6 KiB
C
#ifndef INCLUDED_C_TARJANSCC_H
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#define INCLUDED_C_TARJANSCC_H
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#ifndef INCLUDED_C_DIGRAPH_H
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#include <c_Digraph.h>
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#endif /*INCLUDED_C_DIGRAPH_H*/
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/* ------------------------------------------------------------------------------------------------------------------ */
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/* */
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typedef struct {
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c_bool_t* marked; /* Visited tracking array (size of graph->V) */
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c_size_t* id; /* id[v] = component identifier containing v (0 to count-1) */
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c_size_t* pre; /* pre[v] = preorder index of vertex v */
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c_size_t* low; /* low[v] = low link of vertex v */
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c_size_t* stack; /* Explicit vertex stack buffer for component mapping tracking */
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c_size_t stack_size; /* Current active elements size in stack tracker */
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c_bool_t* on_stack; /* Quick boolean lookup mapping for stack memberships */
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c_size_t pre_counter; /* Preorder index sequencing index variable counter */
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c_size_t count; /* Total number of strongly connected components discovered */
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c_size_t V;
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c_Allocator_t allocator; /* Deep copy of the user-provided allocator */
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} c_TarjanSCC_t;
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/* ------------------------------------------------------------------------------------------------------------------ */
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/* */
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/**
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* @brief Computes strongly connected components for the specified digraph using Tarjan's algorithm.
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* @param allocator Explicit allocator context used to allocate internal routing arrays
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*/
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c_err_t c_TarjanSCC_Init(c_TarjanSCC_t* self, c_Digraph_t* graph, c_Allocator_t* allocator);
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/**
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* @brief Releases internal tracking buffers
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*/
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void c_TarjanSCC_Destroy(c_TarjanSCC_t* self);
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/**
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* @brief Are vertices 'v' and 'w' strongly connected (belong to the same SCC)?
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*/
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C_STATIC_FORCE_INLINE
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c_bool_t c_TarjanSCC_StronglyConnected(c_TarjanSCC_t* self, c_size_t v, c_size_t w) {
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if (!self || !self->id || v >= self->V || w >= self->V) return C_FALSE;
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return self->id[v] == self->id[w];
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}
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/**
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* @brief Returns the component id containing vertex 'v'
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* @return Component integer ID (0 to count-1), or C_SIZE_MAX on boundary check failures
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*/
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C_STATIC_FORCE_INLINE
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c_size_t c_TarjanSCC_GetId(const c_TarjanSCC_t* self, c_size_t v) {
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if (!self || !self->id || v >= self->V) return C_SIZE_MAX;
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return self->id[v];
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}
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/**
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* @brief Returns the total number of strongly connected components
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*/
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C_STATIC_FORCE_INLINE
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c_size_t c_TarjanSCC_GetCount(const c_TarjanSCC_t* self) {
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return self ? self->count : 0;
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}
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#endif /*INCLUDED_C_TARJANSCC_H*/
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