     "metadata": {},
     "source": [
      "## Problem: Implement an algorithm to determine if a string has all unique characters\n",
      "\n",
      "* [Constraints and Assumptions](#Constraints-and-Assumptions)\n",
      "* [Test Cases](#Test-Cases)\n",
      "* [Algorithm 1: Sets and Length Comparison](#Algorithm-1:-Sets-and-Length-Comparison)\n",
      "* [Code: Sets and Length Comparison](#Code:-Sets-and-Length-Comparison)\n",
      "* [Algorithm 2: Hash Map Lookup](#Algorithm-2:-Hash-Map-Lookup)\n",
      "* [Code: Hash Map Lookup](#Code:-Hash-Map-Lookup)\n",
 
</s> remove     "* [Constraints and Assumptions](#Constraints-and-Assumptions)\n",
 </s> add     "* [Constraints](#Constraints)\n", </s> remove     "* [Constraints and Assumptions](#Constraints-and-Assumptions)\n",
 </s> add     "* [Constraints](#Constraints)\n", </s> remove     "* [Constraints and Assumptions](#Constraints-and-Assumptions)\n",
 </s> add     "* [Constraints](#Constraints)\n", </s> remove     "* [Constraints and Assumptions](#Constraints-and-Assumptions)\n",
 </s> add     "* [Constraints](#Constraints)\n", </s> remove     "* [Constraints and Assumptions](#Constraints-and-Assumptions)\n",
 </s> add     "* [Constraints](#Constraints)\n",
    "* [Constraints](#Constraints)\n",
     "metadata": {},
     "source": [
      "## Problem: Implement an algorithm to determine if a string has all unique characters\n",
      "\n",
    "* [Constraints](#Constraints)\n",
      "* [Test Cases](#Test-Cases)\n",
      "* [Algorithm 1: Sets and Length Comparison](#Algorithm-1:-Sets-and-Length-Comparison)\n",
      "* [Code: Sets and Length Comparison](#Code:-Sets-and-Length-Comparison)\n",
      "* [Algorithm 2: Hash Map Lookup](#Algorithm-2:-Hash-Map-Lookup)\n",
      "* [Code: Hash Map Lookup](#Code:-Hash-Map-Lookup)\n",
keep keep keep keep replace keep keep keep keep keep
 Fixed Constraints section label and link anchor. 
arrays_strings/unique_chars/unique_chars.ipynb