count-and-say.json

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            "title": "Count and Say",
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            "content": "<p>The <strong>count-and-say</strong> sequence is a sequence of digit strings defined by the recursive formula:</p>\n\n<ul>\n\t<li><code>countAndSay(1) = &quot;1&quot;</code></li>\n\t<li><code>countAndSay(n)</code> is the way you would &quot;say&quot; the digit string from <code>countAndSay(n-1)</code>, which is then converted into a different digit string.</li>\n</ul>\n\n<p>To determine how you &quot;say&quot; a digit string, split it into the <strong>minimal</strong> number of groups so that each group is a contiguous section all of the <strong>same character.</strong> Then for each group, say the number of characters, then say the character. To convert the saying into a digit string, replace the counts with a number and concatenate every saying.</p>\n\n<p>For example, the saying and conversion for digit string <code>&quot;3322251&quot;</code>:</p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2020/10/23/countandsay.jpg\" style=\"width: 581px; height: 172px;\" />\n<p>Given a positive integer <code>n</code>, return <em>the </em><code>n<sup>th</sup></code><em> term of the <strong>count-and-say</strong> sequence</em>.</p>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 1\n<strong>Output:</strong> &quot;1&quot;\n<strong>Explanation:</strong> This is the base case.\n</pre>\n\n<p><strong>Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 4\n<strong>Output:</strong> &quot;1211&quot;\n<strong>Explanation:</strong>\ncountAndSay(1) = &quot;1&quot;\ncountAndSay(2) = say &quot;1&quot; = one 1 = &quot;11&quot;\ncountAndSay(3) = say &quot;11&quot; = two 1&#39;s = &quot;21&quot;\ncountAndSay(4) = say &quot;21&quot; = one 2 + one 1 = &quot;12&quot; + &quot;11&quot; = &quot;1211&quot;\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</ul>\n",
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                    "code": "class Solution(object):\n    def countAndSay(self, n):\n        \"\"\"\n        :type n: int\n        :rtype: str\n        \"\"\"\n        ",
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                    "code": "/**\n * @param {number} n\n * @return {string}\n */\nvar countAndSay = function(n) {\n    \n};",
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                    "code": "# @param {Integer} n\n# @return {String}\ndef count_and_say(n)\n    \nend",
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                    "code": "func countAndSay(n int) string {\n    \n}",
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                    "code": "impl Solution {\n    pub fn count_and_say(n: i32) -> String {\n        \n    }\n}",
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                    "code": "class Solution {\n\n    /**\n     * @param Integer $n\n     * @return String\n     */\n    function countAndSay($n) {\n        \n    }\n}",
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                    "code": "(define/contract (count-and-say n)\n  (-> exact-integer? string?)\n\n  )",
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                    "code": "-spec count_and_say(N :: integer()) -> unicode:unicode_binary().\ncount_and_say(N) ->\n  .",
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                    "code": "defmodule Solution do\n  @spec count_and_say(n :: integer) :: String.t\n  def count_and_say(n) do\n\n  end\nend",
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            "hints": [
                "The following are the terms from n=1 to n=10 of the count-and-say sequence:\r\n<pre>\r\n 1.     1\r\n 2.     11\r\n 3.     21\r\n 4.     1211\r\n 5.     111221 \r\n 6.     312211\r\n 7.     13112221\r\n 8.     1113213211\r\n 9.     31131211131221\r\n10.     13211311123113112211\r\n</pre>",
                "To generate the <i>n</i><sup>th</sup> term, just <i>count and say</i> the <i>n</i>-1<sup>th</sup> term."
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