feribg · September 15, 2015 01:10 · Sep 15, 2015 · Sep 15, 2015 · Sep 15, 2015 · Sep 15, 2015
diff --git a/test.php b/test.php
@@ -6,6 +6,9 @@
 $arr2 = [3,[4,5,[6],7],8];
 $arr2_test = [3,4,5,6,7,8];
 
+/**
+ * Given an array $arr and a new array $res, this function would flatten $arr into $res using recursion.
+ */
 function flatten(array $arr, &$res){
 	foreach($arr as $el){
 		if(is_array($el)){

diff --git a/test.php b/test.php
@@ -24,7 +24,7 @@ function flatten(array $arr, &$res){
 
 $arr2_rest = [];
 flatten($arr2, $arr2_res);
-assert($arr2_res == $arr2_test);
+assert($arr2_res === $arr2_test);
 var_dump($arr2_test);
 
 ?>
diff --git a/test → test.php b/test → test.php
diff --git a/test b/test
@@ -0,0 +1,30 @@
+<?php
+
+$arr1 = [[1,2,[3]],4]; 
+$arr1_test = [1,2,3,4];
+
+$arr2 = [3,[4,5,[6],7],8];
+$arr2_test = [3,4,5,6,7,8];
+
+function flatten(array $arr, &$res){
+	foreach($arr as $el){
+		if(is_array($el)){
+			flatten($el, $res);
+		}else{
+			$res[] = $el;
+		}
+	}
+}
+
+
+$arr1_res = [];
+flatten($arr1, $arr1_res);
+assert($arr1_res === $arr1_test);
+var_dump($arr1_res);
+
+$arr2_rest = [];
+flatten($arr2, $arr2_res);
+assert($arr2_res == $arr2_test);
+var_dump($arr2_test);
+
+?>