diff --git a/arrays_strings/permutation/permutation_challenge.ipynb b/arrays_strings/permutation/permutation_challenge.ipynb
index eece64f..1f03fc5 100644
--- a/arrays_strings/permutation/permutation_challenge.ipynb
+++ b/arrays_strings/permutation/permutation_challenge.ipynb
@@ -124,6 +124,7 @@
     "        self.assertEqual(func('act', 'cat'), True)\n",
     "        self.assertEqual(func('a ct', 'ca t'), True)\n",
     "        self.assertEqual(func('dog', 'doggo'), False)\n",
+    "        self.assertEqual(func('dogoo', 'dogcc'), False)\n",
     "        print('Success: test_permutation')\n",
     "\n",
     "\n",
diff --git a/arrays_strings/permutation/permutation_solution.ipynb b/arrays_strings/permutation/permutation_solution.ipynb
index 49a7c0b..2e74b07 100644
--- a/arrays_strings/permutation/permutation_solution.ipynb
+++ b/arrays_strings/permutation/permutation_solution.ipynb
@@ -196,6 +196,7 @@
     "        self.assertEqual(func('act', 'cat'), True)\n",
     "        self.assertEqual(func('a ct', 'ca t'), True)\n",
     "        self.assertEqual(func('dog', 'doggo'), False)\n",
+    "        self.assertEqual(func('dogoo', 'dogcc'), False)\n",
     "        print('Success: test_permutation')\n",
     "\n",
     "\n",