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    <p><strong>Why selection algorithm fails:</strong> <br>Note that using selection algorithm is linear in the #elements. Assuming #requests is linear in #elements - it will lead to a quadric solution, and this is why you get time limit exceeded. </p> <p><strong>An alternative approach:</strong> Maintain two heaps: a max heap <code>H1</code> and a min heap <code>H2</code></p> <p>The max heap (<code>H1</code>) will hold the 2/3 lowest numbers while the min heap will gold the 1/3 highest numbers.</p> <p>Now, for each element <code>x</code> you read, check if you need to increase the top 1/3 heap (<code>H2</code>), and if you do: you need to add <code>max{x,H1.max()}</code>. If you added <code>H1.max()</code> - you need to remove it from the heap, and insert <code>x</code> instead. If no addition is needed, check if <code>x</code> is bigger then <code>H2.min()</code>, if it is, remove the min form <code>H2</code>, insert it to <code>H1</code>, and add <code>x</code> to <code>H1</code>.</p> <p><br>Note: the number you are looking for in this solution can be found in <code>O(1)</code> at any time, it is the minimum of the min heap (<code>H2</code>).</p> <p>Total complexity if this solution is <code>O(nlogn + k)</code> - where <code>n</code> is the number of numbers, and <code>k</code> is the total number of "tell the number" requests.</p> <p><strong>Note</strong>: a simpler solution (though probably slower) will be to maintain the list sorted (in a <a href="http://en.wikipedia.org/wiki/Binary_search_tree" rel="nofollow">BST</a> or a <a href="http://en.wikipedia.org/wiki/Skip_list" rel="nofollow">skiplist</a> for example), and use binary search to look for the relevant element.</p> <p><strong>Example:</strong></p> <pre><code>init: H1 = {} H2 = {} input1: H1 = {1} H2 = {} input7: H1={1,7} H2 = {} input 9: //need to add a max, in this case: x &gt; H2.max() -&gt; add x to H2. H1 = {1,7} H2 = {9} tell the number H2.min() = 9 input 21: // 21&gt;9 -&gt; remove H2.min() add it to H1, add x to H2 H1 = {1,7,9} H2 = {21} input 8: H1 = {1,7,8,9} H2 = {21} input 5: //remove max from H1, add max to H2, add x to H1 H1 = {1,7,5,8} H2 = {9,21} tell the number H2.min() = 9 input 11: //remove min from H2, add it to H1, add x to H2. H1 = {1,7,5,8,9} H2 = {11,21} tell the number H2.min() = 11 </code></pre>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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