longestSubstring.ipynb

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    "## Longest Substring\n",
    "\n",
    "Given a string `s`, find the length of the longest substring without repeating characters.\n",
    "\n",
    "#### Example 1:\n",
    "\n",
    "Input: `s = \"abcabcbb\"`\n",
    "\n",
    "Output: `3`\n",
    "\n",
    "Explanation: The answer is \"abc\", with the length of 3.\n",
    "\n",
    "#### Example 2:\n",
    "\n",
    "Input: `s = \"bbbbb\"`\n",
    "\n",
    "Output: `1`\n",
    "\n",
    "Explanation: The answer is \"b\", with the length of 1.\n",
    "\n",
    "#### Example 3:\n",
    "\n",
    "Input: `s = \"pwwkew\"`\n",
    "\n",
    "Output: `3`\n",
    "\n",
    "Explanation: \n",
    "- The answer is \"wke\", with the length of 3.\n",
    "- Notice that the answer must be a substring, \"pwke\" is a subsequence and not a substring."
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    "def lengthOfLongestSubstring(s):\n",
    "\n",
    "    slist = list(s)\n",
    "    #print(len(slist))\n",
    "    \n",
    "    if len(slist) == 0:\n",
    "        return 0\n",
    "    else:\n",
    "        left = 0\n",
    "        right = 1\n",
    "        substr = []\n",
    "        lengths = []\n",
    "\n",
    "        while right < len(slist):\n",
    "            #print(left, right)\n",
    "            if slist[left] not in substr: \n",
    "                substr.append(slist[left])\n",
    "                #print(left, right)\n",
    "            elif slist[right] not in substr:\n",
    "                substr.append(slist[right])\n",
    "                right += 1\n",
    "                #print(left, right)\n",
    "            elif slist[right] in substr:\n",
    "                left += 1\n",
    "                right = left + 1\n",
    "                lengths.append(len(substr))\n",
    "                #print(substr, lengths)\n",
    "                substr = []\n",
    "            #print(substr, lengths)\n",
    "\n",
    "        return max(lengths)\n",
    "        "
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   "source": [
    "s = 'pwwkew'\n",
    "lengthOfLongestSubstring(s)"
   ]
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   "source": [
    "s=' '\n",
    "len(list(s))"
   ]
  }
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