From 013def5142e515696e1f41b36c42486dfa4a1a38 Mon Sep 17 00:00:00 2001
From: Taras Tsugrii <taras.tsugriy@gmail.com>
Date: Sun, 18 Jun 2023 20:49:26 -0500
Subject: [PATCH 1/2] [bruteforce] Fix bruteforce removePoint.

---
 hnswlib/bruteforce.h | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/hnswlib/bruteforce.h b/hnswlib/bruteforce.h
index 30b33ae9..15d10c98 100644
--- a/hnswlib/bruteforce.h
+++ b/hnswlib/bruteforce.h
@@ -84,10 +84,16 @@ class BruteforceSearch : public AlgorithmInterface<dist_t> {
 
 
     void removePoint(labeltype cur_external) {
-        size_t cur_c = dict_external_to_internal[cur_external];
+        std::unique_lock<std::mutex> lock(index_lock);
 
-        dict_external_to_internal.erase(cur_external);
+        auto found = dict_external_to_internal.find(cur_external);
+        if (found == dict_external_to_internal.end()) {
+            return;
+        }
+
+        dict_external_to_internal.erase(found);
 
+        size_t cur_c = found->second;
         labeltype label = *((labeltype*)(data_ + size_per_element_ * (cur_element_count-1) + data_size_));
         dict_external_to_internal[label] = cur_c;
         memcpy(data_ + size_per_element_ * cur_c,

From 1ee95db9aa91a720f241b5aa147019e1e90acbff Mon Sep 17 00:00:00 2001
From: Taras Tsugrii <taras.tsugriy@gmail.com>
Date: Sun, 18 Jun 2023 21:12:51 -0500
Subject: [PATCH 2/2] Use unique_ptr to manage visited_list_pool_.

---
 hnswlib/hnswalg.h | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/hnswlib/hnswalg.h b/hnswlib/hnswalg.h
index 1356ce82..901b1878 100644
--- a/hnswlib/hnswalg.h
+++ b/hnswlib/hnswalg.h
@@ -8,6 +8,7 @@
 #include <assert.h>
 #include <unordered_set>
 #include <list>
+#include <memory>
 
 namespace hnswlib {
 typedef unsigned int tableint;
@@ -33,7 +34,7 @@ class HierarchicalNSW : public AlgorithmInterface<dist_t> {
     double mult_{0.0}, revSize_{0.0};
     int maxlevel_{0};
 
-    VisitedListPool *visited_list_pool_{nullptr};
+    std::unique_ptr<VisitedListPool> visited_list_pool_{nullptr};
 
     // Locks operations with element by label value
     mutable std::vector<std::mutex> label_op_locks_;
@@ -122,7 +123,7 @@ class HierarchicalNSW : public AlgorithmInterface<dist_t> {
 
         cur_element_count = 0;
 
-        visited_list_pool_ = new VisitedListPool(1, max_elements);
+        visited_list_pool_ = std::unique_ptr<VisitedListPool>(new VisitedListPool(1, max_elements));
 
         // initializations for special treatment of the first node
         enterpoint_node_ = -1;
@@ -144,7 +145,6 @@ class HierarchicalNSW : public AlgorithmInterface<dist_t> {
                 free(linkLists_[i]);
         }
         free(linkLists_);
-        delete visited_list_pool_;
     }
 
 
@@ -573,8 +573,7 @@ class HierarchicalNSW : public AlgorithmInterface<dist_t> {
         if (new_max_elements < cur_element_count)
             throw std::runtime_error("Cannot resize, max element is less than the current number of elements");
 
-        delete visited_list_pool_;
-        visited_list_pool_ = new VisitedListPool(1, new_max_elements);
+        visited_list_pool_.reset(new VisitedListPool(1, new_max_elements));
 
         element_levels_.resize(new_max_elements);
 
@@ -724,7 +723,7 @@ class HierarchicalNSW : public AlgorithmInterface<dist_t> {
         std::vector<std::mutex>(max_elements).swap(link_list_locks_);
         std::vector<std::mutex>(MAX_LABEL_OPERATION_LOCKS).swap(label_op_locks_);
 
-        visited_list_pool_ = new VisitedListPool(1, max_elements);
+        visited_list_pool_.reset(new VisitedListPool(1, max_elements));
 
         linkLists_ = (char **) malloc(sizeof(void *) * max_elements);
         if (linkLists_ == nullptr)