From d87b18a56e23cf1d9ac8fbdbdeb78db5dbe1d8bb Mon Sep 17 00:00:00 2001
From: Slava Kim <slava@meteor.com>
Date: Thu, 20 Feb 2014 22:38:56 -0800
Subject: [PATCH] Fix building heap from array

---
 packages/binary-heap/max-heap.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/binary-heap/max-heap.js b/packages/binary-heap/max-heap.js
index 37fc90c941..349dde8030 100644
--- a/packages/binary-heap/max-heap.js
+++ b/packages/binary-heap/max-heap.js
@@ -48,7 +48,8 @@ _.extend(MaxHeap.prototype, {
       self._heapIdx.set(o.id, i);
     });
 
-    for (var i = parentIdx(data.length); i >= 0; i--)
+    // start from the first non-leaf - the parent of the last leaf
+    for (var i = parentIdx(data.length - 1); i >= 0; i--)
       self._downHeap(i);
   },