    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## Problem: Determine if a string s1 is a rotation of another string s2, by calling (only once) a function is_substring\n",
      "\n",
      "* [Constraints](#Constraints)\n",
      "* [Test Cases](#Test-Cases)\n",
      "* [Algorithm](#Algorithm)\n",
      "* [Code](#Code)\n",
 
</s>
    "## Problem: Determine if a string s1 is a rotation of another string s2, by calling (only once) a function is_substring.\n",
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
    "## Problem: Determine if a string s1 is a rotation of another string s2, by calling (only once) a function is_substring.\n",
      "\n",
      "* [Constraints](#Constraints)\n",
      "* [Test Cases](#Test-Cases)\n",
      "* [Algorithm](#Algorithm)\n",
      "* [Code](#Code)\n",
keep keep keep keep replace keep keep keep keep keep
 Fix challenge titles punctuation (#132)
arrays_strings/rotation/rotation_solution.ipynb