minor bug fixes

Author: doganoo

README.md

@@ -3,4 +3,5 @@ A collection of common algorithms implemented in PHP. The collection is based on
 
 The library is in a beta state. Missing something? Create a pull request!
 
-You can find the package on Packagist: https://packagist.org/packages/doganoo/php-algorithms 
+You can find the package on Packagist: https://packagist.org/packages/doganoo/php-algorithms
+ 

src/Datastructure/Graph/Tree/Heap/MinHeap.php

@@ -66,7 +66,7 @@ public function clear(): bool {
     /**
      * @param int $element
      */
-    public function insert(int $element) {
+    public function insert(int $element): void {
         $length = $this->length();
         $this->heap[$length + 1] = $element;
         $currentPosition = $this->length();

src/Datastructure/Maps/IntegerVector.php

@@ -105,7 +105,8 @@ public function get($value) {
             $flag = 1;
             $flag = $flag << $k;
 
-            return (($this->array[$i] & $flag) !== 0);
+            if (isset($this->array[$i])) return (($this->array[$i] & $flag) !== 0);
+            return false;
         }
         return false;
     }
@@ -137,10 +138,6 @@ public function clear($value): bool {
         return false;
     }
 
-    public function printVector() {
-        \print_r($this->array);
-    }
-
     /**
      * @param $object
      * @return int