diff --git a/src/JsonPointer.php b/src/JsonPointer.php
index 08a1d3a..d9fc2e0 100644
--- a/src/JsonPointer.php
+++ b/src/JsonPointer.php
@@ -134,7 +134,7 @@ public static function add(&$holder, $pathItems, $value, $flags = self::RECURSIV
                 } else {
                     if ($flags & self::RECURSIVE_KEY_CREATION && $ref === null) $ref = array();
                     if ('-' === $key) {
-                        $ref = &$ref[];
+                        $ref = &$ref[count($ref)];
                     } else {
                         if (false === $intKey) {
                             if (0 === ($flags & self::TOLERATE_ASSOCIATIVE_ARRAYS)) {
@@ -282,7 +282,6 @@ public static function remove(&$holder, $pathItems, $flags = 0)
                 unset($parent->$refKey);
             } else {
                 $isAssociative = false;
-                $ff = $flags & self::TOLERATE_ASSOCIATIVE_ARRAYS;
                 if ($flags & self::TOLERATE_ASSOCIATIVE_ARRAYS) {
                     $i = 0;
                     foreach ($parent as $index => $value) {
diff --git a/tests/src/Issues/Issue31Test.php b/tests/src/Issues/Issue31Test.php
new file mode 100644
index 0000000..a6e0982
--- /dev/null
+++ b/tests/src/Issues/Issue31Test.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace Swaggest\JsonDiff\Tests\Issues;
+
+use Swaggest\JsonDiff\JsonPatch;
+
+class Issue31Test extends \PHPUnit_Framework_TestCase
+{
+    public function testIssue()
+    {
+        $reportData = json_decode('{}');
+        $patch = JsonPatch::import(json_decode('[{"op":"add","path":"","value":["a","b","c","d"]},{"op":"remove","path":"\/3","value":""},{"op":"add","path":"\/-","value":"e"}]'));
+        $patch->apply($reportData);
+
+        $this->assertSame('["a","b","c","e"]', json_encode($reportData));
+    }
+
+}
\ No newline at end of file