Update others/lru_cache.cpp

Co-authored-by: David Leal <halfpacho@gmail.com>

others/lru_cache.cpp

@@ -50,6 +50,11 @@
 #include <list>           /// for std::list
 #include <unordered_map>  /// for std::unordered_map
 
+/**
+ * @namespace others
+ * @brief Other algorithms
+ */
+namespace others {
 /**
  * @namespace lru_cache
  * @brief Implementation of LRU caching algorithm