diff --git a/stacks_queues/n_stacks/n_stacks_challenge.ipynb b/stacks_queues/n_stacks/n_stacks_challenge.ipynb
index 2b1ca82..d527520 100644
--- a/stacks_queues/n_stacks/n_stacks_challenge.ipynb
+++ b/stacks_queues/n_stacks/n_stacks_challenge.ipynb
@@ -35,6 +35,14 @@
     "## Constraints\n",
     "\n",
     "* Are the stacks and array a fixed size?\n",
+    "    * Yes\n",
+    "* Are the stacks equally sized?\n",
+    "    * Yes\n",
+    "* Does pushing to a full stack result in an exception?\n",
+    "    * Yes\n",
+    "* Does popping from an empty stack result in an exception?\n",
+    "    * Yes\n",
+    "* Can we assume the user passed in stack index is valid?\n",
     "    * Yes"
    ]
   },
@@ -176,21 +184,21 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.10"
+   "pygments_lexer": "ipython3",
+   "version": "3.5.0"
   }
  },
  "nbformat": 4,
diff --git a/stacks_queues/n_stacks/n_stacks_solution.ipynb b/stacks_queues/n_stacks/n_stacks_solution.ipynb
index 1f248a6..42fb13a 100644
--- a/stacks_queues/n_stacks/n_stacks_solution.ipynb
+++ b/stacks_queues/n_stacks/n_stacks_solution.ipynb
@@ -34,6 +34,14 @@
     "## Constraints\n",
     "\n",
     "* Are the stacks and array a fixed size?\n",
+    "    * Yes\n",
+    "* Are the stacks equally sized?\n",
+    "    * Yes\n",
+    "* Does pushing to a full stack result in an exception?\n",
+    "    * Yes\n",
+    "* Does popping from an empty stack result in an exception?\n",
+    "    * Yes\n",
+    "* Can we assume the user passed in stack index is valid?\n",
     "    * Yes"
    ]
   },
@@ -249,7 +257,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.4.3"
+   "version": "3.5.0"
   }
  },
  "nbformat": 4,