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            "title": "K-th Symbol in Grammar",
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            "content": "<p>We build a table of <code>n</code> rows (<strong>1-indexed</strong>). We start by writing <code>0</code> in the <code>1<sup>st</sup></code> row. Now in every subsequent row, we look at the previous row and replace each occurrence of <code>0</code> with <code>01</code>, and each occurrence of <code>1</code> with <code>10</code>.</p>\n\n<ul>\n\t<li>For example, for <code>n = 3</code>, the <code>1<sup>st</sup></code> row is <code>0</code>, the <code>2<sup>nd</sup></code> row is <code>01</code>, and the <code>3<sup>rd</sup></code> row is <code>0110</code>.</li>\n</ul>\n\n<p>Given two integer <code>n</code> and <code>k</code>, return the <code>k<sup>th</sup></code> (<strong>1-indexed</strong>) symbol in the <code>n<sup>th</sup></code> row of a table of <code>n</code> rows.</p>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 1, k = 1\n<strong>Output:</strong> 0\n<strong>Explanation:</strong> row 1: <u>0</u>\n</pre>\n\n<p><strong>Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 2, k = 1\n<strong>Output:</strong> 0\n<strong>Explanation:</strong> \nrow 1: 0\nrow 2: <u>0</u>1\n</pre>\n\n<p><strong>Example 3:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 2, k = 2\n<strong>Output:</strong> 1\n<strong>Explanation:</strong> \nrow 1: 0\nrow 2: 0<u>1</u>\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 &lt;= n &lt;= 30</code></li>\n\t<li><code>1 &lt;= k &lt;= 2<sup>n - 1</sup></code></li>\n</ul>\n",
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                    "code": "class Solution(object):\n    def kthGrammar(self, n, k):\n        \"\"\"\n        :type n: int\n        :type k: int\n        :rtype: int\n        \"\"\"\n        ",
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                "Try to represent the current (N, K) in terms of some (N-1, prevK).  What is prevK ?"
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