gl: contiguous alg containers

Author: SpectraL519

include/gl/algorithm/templates/bfs.hpp

@@ -8,7 +8,7 @@
 #include "gl/algorithm/traits.hpp"
 #include "gl/algorithm/util.hpp"
 
-#include <queue>
+#include <vector>
 
 namespace gl::algorithm {
 
@@ -35,14 +35,16 @@ bool bfs(
         return false;
 
     // prepare the node queue
-    std::queue<search_node<G>> q;
-    for (const auto& node : initial_queue_content)
-        q.push(node);
+    std::vector<search_node<G>> q;
+    q.reserve(graph.n_vertices());
+    q.insert(
+        q.end(), std::ranges::begin(initial_queue_content), std::ranges::end(initial_queue_content)
+    );
+    std::size_t q_head = 0uz;
 
     // search the graph
-    while (not q.empty()) {
-        const search_node node = q.front();
-        q.pop();
+    while (q_head < q.size()) {
+        const search_node node = q[q_head++];
 
         if constexpr (not traits::c_empty_callback<VisitVertexPredicate>)
             if (not visit_vertex_pred(node.vertex_id))
@@ -57,11 +59,13 @@ bool bfs(
 
         for (const auto& edge : graph.out_edges(node.vertex_id)) {
             const auto target_vertex_id = edge.other(node.vertex_id);
+
             const auto enqueue = enqueue_vertex_pred(target_vertex_id, edge);
             if (enqueue == decision::abort)
                 return false;
+
             if (enqueue)
-                q.emplace(target_vertex_id, node.vertex_id);
+                q.emplace_back(target_vertex_id, node.vertex_id);
         }
 
         if constexpr (not traits::c_empty_callback<PostVisitCallback>)

include/gl/algorithm/templates/dfs.hpp

@@ -8,7 +8,7 @@
 #include "gl/algorithm/traits.hpp"
 #include "gl/algorithm/util.hpp"
 
-#include <stack>
+#include <vector>
 
 namespace gl::algorithm {
 
@@ -35,14 +35,16 @@ bool dfs(
         return false;
 
     // prepare the node stack
-    std::stack<search_node<G>> s;
-    for (const auto& node : initial_stack_content)
-        s.push(node);
+    std::vector<search_node<G>> s;
+    s.reserve(graph.n_vertices());
+    s.insert(
+        s.end(), std::ranges::begin(initial_stack_content), std::ranges::end(initial_stack_content)
+    );
 
     // search the graph
     while (not s.empty()) {
-        const auto node = s.top();
-        s.pop();
+        const auto node = s.back();
+        s.pop_back();
 
         if constexpr (not traits::c_empty_callback<VisitVertexPredicate>)
             if (not visit_vertex_pred(node.vertex_id))
@@ -57,8 +59,13 @@ bool dfs(
 
         for (const auto& edge : graph.out_edges(node.vertex_id)) {
             const auto target_vertex_id = edge.other(node.vertex_id);
-            if (enqueue_vertex_pred(target_vertex_id, edge))
-                s.emplace(target_vertex_id, node.vertex_id);
+
+            const auto enqueue = enqueue_vertex_pred(target_vertex_id, edge);
+            if (enqueue == decision::abort)
+                return false;
+
+            if (enqueue)
+                s.emplace_back(target_vertex_id, node.vertex_id);
         }
 
         if constexpr (not traits::c_empty_callback<PostVisitCallback>)

include/gl/algorithm/traversal/depth_first_search.hpp

@@ -35,7 +35,7 @@ return_type<Result, predecessors_map<G>> depth_first_search(
             init_range<G>(root_vertex_id),
             default_visit_vertex_predicate(visited),
             default_visit_callback<G, Result>(visited, pred_map),
-            default_enqueue_vertex_predicate<G>(visited),
+            default_enqueue_vertex_predicate<G, true>(visited),
             pre_visit,
             post_visit
         );
@@ -47,7 +47,7 @@ return_type<Result, predecessors_map<G>> depth_first_search(
                 init_range<G>(root_id),
                 default_visit_vertex_predicate(visited),
                 default_visit_callback<G, Result>(visited, pred_map),
-                default_enqueue_vertex_predicate<G>(visited),
+                default_enqueue_vertex_predicate<G, true>(visited),
                 pre_visit,
                 post_visit
             );