From 48462723932e2dfbdcc41c2006fd675d701e6da5 Mon Sep 17 00:00:00 2001
From: Martin Sumner <martin.sumner@adaptip.co.uk>
Date: Sat, 21 Jan 2017 01:48:38 +0000
Subject: [PATCH] Build more efficiently
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Don’t use ++ to build the tree
---
 src/leveled_tree.erl | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/leveled_tree.erl b/src/leveled_tree.erl
index 792c05d..6f50c28 100644
--- a/src/leveled_tree.erl
+++ b/src/leveled_tree.erl
@@ -26,7 +26,7 @@
 
 -include_lib("eunit/include/eunit.hrl").
 
--define(SKIP_WIDTH, 32).
+-define(SKIP_WIDTH, 16).
 
 
 %%%============================================================================
@@ -99,12 +99,12 @@ empty() ->
 
 
 from_orderedlist([], TmpList, _L) ->
-    gb_trees:from_orddict(TmpList);
+    gb_trees:from_orddict(lists:reverse(TmpList));
 from_orderedlist(OrdList, TmpList, L) ->
     SubLL = min(?SKIP_WIDTH, L),
     {Head, Tail} = lists:split(SubLL, OrdList),
     {LastK, _LastV} = lists:last(Head),
-    from_orderedlist(Tail, TmpList ++ [{LastK, Head}], L - SubLL).
+    from_orderedlist(Tail, [{LastK, Head}|TmpList], L - SubLL).
     
 lookup_match(_Key, []) ->
     none;
@@ -276,7 +276,7 @@ tree_search_test() ->
     
     
 tree_test() ->
-    N = 2000,
+    N = 4000,
     KL = lists:ukeysort(1, generate_randomkeys(1, N, 1, N div 5)),
     
     OS = ets:new(test, [ordered_set, private]),