151. Reverse Words in a String.ipynb

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    "'''\n",
    "151. Reverse Words in a String\n",
    "Given an input string s, reverse the order of the words.\n",
    "\n",
    "A word is defined as a sequence of non-space characters. The words in s will be separated by at least one space.\n",
    "\n",
    "Return a string of the words in reverse order concatenated by a single space.\n",
    "\n",
    "Note that s may contain leading or trailing spaces or multiple spaces between two words. \n",
    "The returned string should only have a single space separating the words. Do not include any extra spaces.\n",
    "\n",
    "\n",
    "Example 1:\n",
    "Input: s = \"the sky is blue\"\n",
    "Output: \"blue is sky the\"\n",
    "\n",
    "Example 2:\n",
    "Input: s = \"  hello world  \"\n",
    "Output: \"world hello\"\n",
    "Explanation: Your reversed string should not contain leading or trailing spaces.\n",
    "\n",
    "Example 3:\n",
    "Input: s = \"a good   example\"\n",
    "Output: \"example good a\"\n",
    "Explanation: You need to reduce multiple spaces between two words to a single space in the reversed string.\n",
    "\n",
    "Time/Space Complexity:\n",
    "\n",
    "Time - O(N)\n",
    "\n",
    "Space - O(N)\n",
    "'''\n",
    "\n",
    "class Solution:\n",
    "    def reverseWords(self, s: str) -> str:\n",
    "        \n",
    "        s = s.strip()\n",
    "        \n",
    "        left , right = 0, len(s)-1\n",
    "        \n",
    "        q = deque()\n",
    "        word = []\n",
    "        \n",
    "        while left <= right:\n",
    "            \n",
    "            if s[left] == \" \" and word:\n",
    "                temp = ''.join(word)\n",
    "                q.appendleft(temp)\n",
    "                word = []\n",
    "            \n",
    "            elif s[left] != \" \":\n",
    "                word.append(s[left])\n",
    "                \n",
    "            left += 1 \n",
    "        \n",
    "        q.appendleft(''.join(word))    \n",
    "            \n",
    "        return ' '.join(q)\n",
    "        \n",
    "        "
   ]
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