algorithms/290-word-pattern.ipynb

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    "### [单词规律](https://leetcode-cn.com/problems/word-pattern/)\n",
    "\n",
    "给定一种规律`pattern`和一个字符串`str`，判断`str`是否遵循相同的规律。\n",
    "\n",
    "这里的 遵循 指完全匹配，例如， `pattern`里的每个字母和字符串`str`中的每个非空单词之间存在着双向连接的对应规律。\n",
    "\n",
    "#### 示例1:\n",
    "```\n",
    "输入: pattern = \"abba\", str = \"dog cat cat dog\"\n",
    "输出: true\n",
    "```\n",
    "\n",
    "#### 示例 2:\n",
    "```\n",
    "输入:pattern = \"abba\", str = \"dog cat cat fish\"\n",
    "输出: false\n",
    "```\n",
    "\n",
    "#### 示例 3:\n",
    "```\n",
    "输入: pattern = \"aaaa\", str = \"dog cat cat dog\"\n",
    "输出: false\n",
    "```\n",
    "\n",
    "#### 示例 4:\n",
    "```\n",
    "输入: pattern = \"abba\", str = \"dog dog dog dog\"\n",
    "输出: false\n",
    "```\n",
    "\n",
    "#### 说明:\n",
    "- 你可以假设`pattern`只包含小写字母，`str`包含了由单个空格分隔的小写字母。 "
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    "def wordPattern(pattern: str, s: str) -> bool:\n",
    "    words = s.split()\n",
    "    m, n = len(pattern), len(words)\n",
    "    if m != n:\n",
    "        return False\n",
    "    \n",
    "    mapping = map(lambda i: (pattern[i], words[i]), range(n))\n",
    "    c2w, w2c = {}, {}\n",
    "    for c, w in mapping:\n",
    "        if c in c2w:\n",
    "            if w != c2w[c]:\n",
    "                return False\n",
    "        else:\n",
    "            c2w[c] = w\n",
    "            \n",
    "        if w in w2c:\n",
    "            if c != w2c[w]:\n",
    "                return False\n",
    "        else:\n",
    "            w2c[w] = c\n",
    "    return True"
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   "source": [
    "wordPattern(\"abba\", \"dog cat cat dog\")"
   ]
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    "wordPattern(\"abba\", \"dog cat cat fish\")"
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    "wordPattern(\"abbc\", \"dog cat cat fish\")"
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   "source": [
    "wordPattern(\"abba\", \"dog dog dog dog\")"
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