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<p>An integer <code>n</code> is <strong>strictly palindromic</strong> if, for <strong>every</strong> base <code>b</code> between <code>2</code> and <code>n - 2</code> (<strong>inclusive</strong>), the string representation of the integer <code>n</code> in base <code>b</code> is <strong>palindromic</strong>.</p>
<p>Given an integer <code>n</code>, return <code>true</code> <em>if </em><code>n</code><em> is <strong>strictly palindromic</strong> and </em><code>false</code><em> otherwise</em>.</p>
<p>A string is <strong>palindromic</strong> if it reads the same forward and backward.</p>
<p>&nbsp;</p>
<p><strong>Example 1:</strong></p>
<pre>
<strong>Input:</strong> n = 9
<strong>Output:</strong> false
<strong>Explanation:</strong> In base 2: 9 = 1001 (base 2), which is palindromic.
In base 3: 9 = 100 (base 3), which is not palindromic.
Therefore, 9 is not strictly palindromic so we return false.
Note that in bases 4, 5, 6, and 7, n = 9 is also not palindromic.
</pre>
<p><strong>Example 2:</strong></p>
<pre>
<strong>Input:</strong> n = 4
<strong>Output:</strong> false
<strong>Explanation:</strong> We only consider base 2: 4 = 100 (base 2), which is not palindromic.
Therefore, we return false.
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>4 &lt;= n &lt;= 10<sup>5</sup></code></li>
</ul>

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<p>Given a <strong>0-indexed</strong> integer array <code>nums</code>, determine whether there exist <strong>two</strong> subarrays of length <code>2</code> with <strong>equal</strong> sum. Note that the two subarrays must begin at <strong>different</strong> indices.</p>
<p>Return <code>true</code><em> if these subarrays exist, and </em><code>false</code><em> otherwise.</em></p>
<p>A <b>subarray</b> is a contiguous non-empty sequence of elements within an array.</p>
<p>&nbsp;</p>
<p><strong>Example 1:</strong></p>
<pre>
<strong>Input:</strong> nums = [4,2,4]
<strong>Output:</strong> true
<strong>Explanation:</strong> The subarrays with elements [4,2] and [2,4] have the same sum of 6.
</pre>
<p><strong>Example 2:</strong></p>
<pre>
<strong>Input:</strong> nums = [1,2,3,4,5]
<strong>Output:</strong> false
<strong>Explanation:</strong> No two subarrays of size 2 have the same sum.
</pre>
<p><strong>Example 3:</strong></p>
<pre>
<strong>Input:</strong> nums = [0,0,0]
<strong>Output:</strong> true
<strong>Explanation:</strong> The subarrays [nums[0],nums[1]] and [nums[1],nums[2]] have the same sum of 0.
Note that even though the subarrays have the same content, the two subarrays are considered different because they are in different positions in the original array.
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>2 &lt;= nums.length &lt;= 1000</code></li>
<li><code>-10<sup>9</sup> &lt;= nums[i] &lt;= 10<sup>9</sup></code></li>
</ul>

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<p>Given two strings <code>needle</code> and <code>haystack</code>, return the index of the first occurrence of <code>needle</code> in <code>haystack</code>, or <code>-1</code> if <code>needle</code> is not part of <code>haystack</code>.</p>
<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre>
<strong>Input:</strong> haystack = &quot;sadbutsad&quot;, needle = &quot;sad&quot;
<strong>Output:</strong> 0
<strong>Explanation:</strong> &quot;sad&quot; occurs at index 0 and 6.
The first occurrence is at index 0, so we return 0.
</pre>
<p><strong class="example">Example 2:</strong></p>
<pre>
<strong>Input:</strong> haystack = &quot;leetcode&quot;, needle = &quot;leeto&quot;
<strong>Output:</strong> -1
<strong>Explanation:</strong> &quot;leeto&quot; did not occur in &quot;leetcode&quot;, so we return -1.
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>1 &lt;= haystack.length, needle.length &lt;= 10<sup>4</sup></code></li>
<li><code>haystack</code> and <code>needle</code> consist of only lowercase English characters.</li>
</ul>

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<p>You are given a <strong>0-indexed</strong> <code>m x n</code> binary matrix <code>mat</code> and an integer <code>cols</code>, which denotes the number of columns you must choose.</p>
<p>A row is <strong>covered</strong> by a set of columns if each cell in the row that has a value of <code>1</code> also lies in one of the columns of the chosen set.</p>
<p>Return <em>the <strong>maximum</strong> number of rows that can be <strong>covered</strong> by a set of </em><code>cols</code><em> columns.</em></p>
<p>&nbsp;</p>
<p><strong>Example 1:</strong></p>
<p><strong><img alt="" src="https://assets.leetcode.com/uploads/2022/07/14/rowscovered.png" style="width: 250px; height: 417px;" /></strong></p>
<pre>
<strong>Input:</strong> mat = [[0,0,0],[1,0,1],[0,1,1],[0,0,1]], cols = 2
<strong>Output:</strong> 3
<strong>Explanation:</strong>
As shown in the diagram above, one possible way of covering 3 rows is by selecting the 0th and 2nd columns.
It can be shown that no more than 3 rows can be covered, so we return 3.
</pre>
<p><strong>Example 2:</strong></p>
<p><strong><img alt="" src="https://assets.leetcode.com/uploads/2022/07/14/rowscovered2.png" style="width: 83px; height: 247px;" /></strong></p>
<pre>
<strong>Input:</strong> mat = [[1],[0]], cols = 1
<strong>Output:</strong> 2
<strong>Explanation:</strong>
Selecting the only column will result in both rows being covered, since the entire matrix is selected.
Therefore, we return 2.
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>m == mat.length</code></li>
<li><code>n == mat[i].length</code></li>
<li><code>1 &lt;= m, n &lt;= 12</code></li>
<li><code>mat[i][j]</code> is either <code>0</code> or <code>1</code>.</li>
<li><code>1 &lt;= cols &lt;= n</code></li>
</ul>

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<p>You have <code>n</code> robots. You are given two <strong>0-indexed</strong> integer arrays, <code>chargeTimes</code> and <code>runningCosts</code>, both of length <code>n</code>. The <code>i<sup>th</sup></code> robot costs <code>chargeTimes[i]</code> units to charge and costs <code>runningCosts[i]</code> units to run. You are also given an integer <code>budget</code>.</p>
<p>The <strong>total cost</strong> of running <code>k</code> chosen robots is equal to <code>max(chargeTimes) + k * sum(runningCosts)</code>, where <code>max(chargeTimes)</code> is the largest charge cost among the <code>k</code> robots and <code>sum(runningCosts)</code> is the sum of running costs among the <code>k</code> robots.</p>
<p>Return<em> the <strong>maximum</strong> number of <strong>consecutive</strong> robots you can run such that the total cost <strong>does not</strong> exceed </em><code>budget</code>.</p>
<p>&nbsp;</p>
<p><strong>Example 1:</strong></p>
<pre>
<strong>Input:</strong> chargeTimes = [3,6,1,3,4], runningCosts = [2,1,3,4,5], budget = 25
<strong>Output:</strong> 3
<strong>Explanation:</strong>
It is possible to run all individual and consecutive pairs of robots within budget.
To obtain answer 3, consider the first 3 robots. The total cost will be max(3,6,1) + 3 * sum(2,1,3) = 6 + 3 * 6 = 24 which is less than 25.
It can be shown that it is not possible to run more than 3 consecutive robots within budget, so we return 3.
</pre>
<p><strong>Example 2:</strong></p>
<pre>
<strong>Input:</strong> chargeTimes = [11,12,19], runningCosts = [10,8,7], budget = 19
<strong>Output:</strong> 0
<strong>Explanation:</strong> No robot can be run that does not exceed the budget, so we return 0.
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>chargeTimes.length == runningCosts.length == n</code></li>
<li><code>1 &lt;= n &lt;= 5 * 10<sup>4</sup></code></li>
<li><code>1 &lt;= chargeTimes[i], runningCosts[i] &lt;= 10<sup>5</sup></code></li>
<li><code>1 &lt;= budget &lt;= 10<sup>15</sup></code></li>
</ul>