fix(heap): some insert fixes

src/heap/vieter_heap.c

@@ -14,7 +14,7 @@ uint64_t vieter_heap_size(vieter_heap *heap) {
   vieter_heap_tree *tree = heap->tree;
 
   while (tree != NULL) {
-    size |= 1 << tree->order;
+    size |= (uint64_t)1 << tree->order;
 
     tree = tree->next;
   }
@@ -22,14 +22,25 @@ uint64_t vieter_heap_size(vieter_heap *heap) {
   return size;
 }
 
-void vieter_heap_free(vieter_heap *heap) {}
+void vieter_heap_free(vieter_heap *heap) {
+  vieter_heap_tree *tree = heap->tree;
+  vieter_heap_tree *next;
+
+  while (tree != NULL) {
+    next = tree->next;
+    vieter_heap_tree_free(tree);
+    tree = next;
+  }
+
+  free(heap);
+}
 
 vieter_heap_error vieter_heap_insert(vieter_heap *heap, uint64_t key,
                                      void *data) {
   vieter_heap_node *new_node = vieter_heap_node_init();
   new_node->key = key;
   new_node->data = data;
-  vieter_heap_tree *new_tree = vieter_heap_tree_init(new_node, NULL, 1);
+  vieter_heap_tree *new_tree = vieter_heap_tree_init(new_node, NULL, 0);
 
   if (heap->tree == NULL) {
     heap->tree = new_tree;
@@ -41,6 +52,18 @@ vieter_heap_error vieter_heap_insert(vieter_heap *heap, uint64_t key,
 }
 
 vieter_heap_error vieter_heap_pop(void **out, vieter_heap *heap) {
+  if (heap->tree == NULL) {
+    return vieter_heap_empty;
+  }
+
+  if (heap->tree->order == 0) {
+      *out = heap->tree->root->data;
+      vieter_heap_tree_free(heap->tree);
+      heap->tree = NULL;
+
+      return vieter_heap_ok;
+  }
+
   return vieter_heap_ok;
 }
 
@@ -49,17 +72,17 @@ vieter_heap_error vieter_heap_peek(void **out, vieter_heap *heap) {
     return vieter_heap_empty;
   }
 
-  uint64_t smallest_key;
-
   vieter_heap_tree *tree = heap->tree;
+  uint64_t smallest_key = tree->root->key;
+  *out = tree->root->data;
+
+  while (tree->next != NULL) {
+    tree = tree->next;
 
-  while (tree != NULL) {
     if (tree->root->key < smallest_key) {
       smallest_key = tree->root->key;
       *out = tree->root->data;
     }
-
-    tree = tree->next;
   }
 
   return vieter_heap_ok;

src/heap/vieter_heap_tree.c

@@ -4,9 +4,39 @@ vieter_heap_node *vieter_heap_node_init() {
   return calloc(1, sizeof(vieter_heap_node));
 }
 
+void vieter_heap_node_free(vieter_heap_node *node) { free(node); }
+
+void vieter_heap_tree_free(vieter_heap_tree *tree) {
+  uint64_t size = 1;
+  vieter_heap_node **stack =
+      malloc(((uint64_t)1 << tree->order) * sizeof(vieter_heap_node *));
+  stack[0] = tree->root;
+
+  vieter_heap_node *node;
+
+  while (size > 0) {
+    node = stack[size - 1];
+    size--;
+
+    if (node->largest_order != NULL) {
+      stack[size] = node->largest_order;
+      size++;
+    }
+
+    if (node->next_largest_order != NULL) {
+      stack[size] = node->next_largest_order;
+      size++;
+    }
+
+    vieter_heap_node_free(node);
+  }
+
+  free(stack);
+  free(tree);
+}
+
 vieter_heap_tree *vieter_heap_tree_init(vieter_heap_node *root,
-                                        vieter_heap_tree *next,
-                                        uint64_t order) {
+                                        vieter_heap_tree *next, uint8_t order) {
   vieter_heap_tree *tree = malloc(sizeof(vieter_heap_tree));
 
   tree->root = root;
@@ -54,7 +84,7 @@ vieter_heap_tree *vieter_heap_tree_merge_same_order(vieter_heap_tree *tree_a,
 
 vieter_heap_tree *vieter_heap_tree_merge(vieter_heap_tree *tree_a,
                                          vieter_heap_tree *tree_b) {
-  vieter_heap_tree *tree, *target;
+  vieter_heap_tree *tree, *target, *out;
 
   if (tree_a->order <= tree_b->order) {
     target = tree_a;
@@ -67,7 +97,7 @@ vieter_heap_tree *vieter_heap_tree_merge(vieter_heap_tree *tree_a,
   vieter_heap_tree *next_tree, *next_target;
   vieter_heap_tree *previous_target = NULL;
 
-  while (target != NULL && target != NULL) {
+  while (target != NULL && tree != NULL) {
     if (target->order == tree->order) {
       next_tree = tree->next;
       next_target = target->next;
@@ -76,38 +106,52 @@ vieter_heap_tree *vieter_heap_tree_merge(vieter_heap_tree *tree_a,
 
       target->next = next_target;
 
-      if (previous_target != NULL) {
-        previous_target->next = target;
-      }
-
-      tree = next_tree;
-
       // If this merge produces a binomial tree whose size is already in
-      // target, it will be the next target. Therefore, we can target's
+      // target, it will be the next target. Therefore, we can  merge target's
       // trees until we no longer have a duplicate depth.
       while (target->next != NULL && target->next->order == target->order) {
-        next_target = target->next;
+        next_target = target->next->next;
         target = vieter_heap_tree_merge_same_order(target, target->next);
         target->next = next_target;
       }
+
+      if (previous_target != NULL) {
+        previous_target->next = target;
+      } else {
+        out = target;
+      }
+
+      tree = next_tree;
     } else if (target->order > tree->order) {
+        next_tree = tree->next;
+
       if (previous_target == NULL) {
         previous_target = tree;
+        out = tree;
       } else {
         previous_target->next = tree;
       }
 
       tree->next = target;
-
-      tree = tree->next;
+      tree = next_tree;
     } else {
+      if (previous_target == NULL) {
+        out = target;
+      }
+
       previous_target = target;
       target = target->next;
     }
   }
 
   // Append final part of tree to target
-  target->next = tree;
+  if (target == NULL) {
+    previous_target->next = tree;
+  }
+
+  return out;
+}
+
+vieter_heap_tree *vieter_heap_tree_pop(vieter_heap_tree *tree) {
 
-  return target;
 }

src/heap/vieter_heap_tree.h

@@ -16,16 +16,23 @@ vieter_heap_node *vieter_heap_node_init();
 void vieter_heap_node_free(vieter_heap_node *node);
 
 typedef struct vieter_heap_tree {
-    uint64_t order;
+    uint8_t order;
     vieter_heap_node *root;
     struct vieter_heap_tree *next;
 } vieter_heap_tree;
 
-vieter_heap_tree *vieter_heap_tree_init(vieter_heap_node *root, vieter_heap_tree *next, uint64_t order);
+vieter_heap_tree *vieter_heap_tree_init(vieter_heap_node *root, vieter_heap_tree *next, uint8_t order);
+
+/*
+ * Deallocate a tree object, along with its underlying tree structure.
+ */
+void vieter_heap_tree_free(vieter_heap_tree *tree);
 
 vieter_heap_tree *vieter_heap_tree_merge(vieter_heap_tree *tree_a, vieter_heap_tree *tree_b);
 
 vieter_heap_tree *vieter_heap_tree_merge_same_order(vieter_heap_tree *tree_a,
                                                     vieter_heap_tree *tree_b);
 
+vieter_heap_tree *vieter_heap_tree_pop(vieter_heap_tree *tree);
+
 #endif