<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:content="http://purl.org/rss/1.0/modules/content/"><channel><title>Brute Force on Kelly Dev</title><link>https://kelly-chui.github.io/tags/brute-force/</link><description>Recent content in Brute Force on Kelly Dev</description><generator>Hugo</generator><language>en-us</language><lastBuildDate>Thu, 06 Aug 2026 13:32:20 +0900</lastBuildDate><atom:link href="https://kelly-chui.github.io/tags/brute-force/index.xml" rel="self" type="application/rss+xml"/><item><title>Leetcode 3345. Smallest Divisible Digit Product I</title><link>https://kelly-chui.github.io/ps/2026/ps-leetcode-3345-smallest-divisible-digit-product-i/</link><pubDate>Thu, 06 Aug 2026 13:32:20 +0900</pubDate><guid>https://kelly-chui.github.io/ps/2026/ps-leetcode-3345-smallest-divisible-digit-product-i/</guid><description>&lt;h2 id="문제"&gt;문제&lt;/h2&gt;
&lt;p&gt;&lt;a href="https://leetcode.com/problems/smallest-divisible-digit-product-i"&gt;https://leetcode.com/problems/smallest-divisible-digit-product-i&lt;/a&gt;&lt;/p&gt;
&lt;h2 id="풀이"&gt;풀이&lt;/h2&gt;
&lt;p&gt;&lt;code&gt;n&lt;/code&gt;보다 큰 수 중에서 각 자리수의 곱이 &lt;code&gt;t&lt;/code&gt;로 나눌 수 있는(나머지가 0인 ) 가장 작은 수를 리턴해야 한다.&lt;/p&gt;
&lt;p&gt;문제의 제약조건이 $1 &amp;lt;= n &amp;lt;= 100$, $1 &amp;lt;= t &amp;lt;= 10$ 이라서 모든 수를 찾아봐도 된다.&lt;/p&gt;
&lt;p&gt;정수의 각 자리수를 모두 곱한 수를 구하는 로직만 구현한 후에, &lt;code&gt;n&lt;/code&gt; 부터 시작해서 숫자를 1씩 증가시키면서 &lt;code&gt;t&lt;/code&gt;로 나눈 나머지를 구해서 찾으면 된다.&lt;/p&gt;
&lt;h2 id="코드"&gt;코드&lt;/h2&gt;
&lt;div class="code-theme-github"&gt;&lt;div class="highlight"&gt;&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-python" data-lang="python"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="k"&gt;class&lt;/span&gt; &lt;span class="nc"&gt;Solution&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;def&lt;/span&gt; &lt;span class="nf"&gt;smallestNumber&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="bp"&gt;self&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;n&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="nb"&gt;int&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="nb"&gt;int&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt; &lt;span class="o"&gt;-&amp;gt;&lt;/span&gt; &lt;span class="nb"&gt;int&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;def&lt;/span&gt; &lt;span class="nf"&gt;productDigits&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;x&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="nb"&gt;int&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt; &lt;span class="o"&gt;-&amp;gt;&lt;/span&gt; &lt;span class="nb"&gt;int&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;product&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="mi"&gt;1&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;while&lt;/span&gt; &lt;span class="n"&gt;x&lt;/span&gt; &lt;span class="o"&gt;&amp;gt;&lt;/span&gt; &lt;span class="mi"&gt;0&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;product&lt;/span&gt; &lt;span class="o"&gt;*=&lt;/span&gt; &lt;span class="n"&gt;x&lt;/span&gt; &lt;span class="o"&gt;%&lt;/span&gt; &lt;span class="mi"&gt;10&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;x&lt;/span&gt; &lt;span class="o"&gt;//=&lt;/span&gt; &lt;span class="mi"&gt;10&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="n"&gt;product&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;answer&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;n&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;while&lt;/span&gt; &lt;span class="n"&gt;productDigits&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;answer&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt; &lt;span class="o"&gt;%&lt;/span&gt; &lt;span class="n"&gt;t&lt;/span&gt; &lt;span class="o"&gt;!=&lt;/span&gt; &lt;span class="mi"&gt;0&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;answer&lt;/span&gt; &lt;span class="o"&gt;+=&lt;/span&gt; &lt;span class="mi"&gt;1&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="n"&gt;answer&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;&lt;/div&gt;</description></item><item><title>BOJ 14658. 하늘에서 별똥별이 빗발친다</title><link>https://kelly-chui.github.io/ps/2024/ps-boj-14658-shooting-stars/</link><pubDate>Sun, 07 Apr 2024 00:00:00 +0000</pubDate><guid>https://kelly-chui.github.io/ps/2024/ps-boj-14658-shooting-stars/</guid><description>&lt;h2 id="문제"&gt;문제&lt;/h2&gt;
&lt;p&gt;&lt;a href="https://www.acmicpc.net/problem/14658"&gt;https://www.acmicpc.net/problem/14658&lt;/a&gt;&lt;/p&gt;
&lt;h2 id="풀이"&gt;풀이&lt;/h2&gt;
&lt;p&gt;우선 최악의 경우를 생각해보자. N, M이 각각 500,000 이고, L은 1, K가 100일 때가 최악인 경우가 된다. 이 상태에서 모든 경우의 수를 확인하려면 별의 위치를 250,000,000,000,000번 확인해야 한다. 따라서 모든 경우의 수를 판단하는건 불가능 하다.&lt;/p&gt;
&lt;p&gt;따라서 트램펄린을 설치할 위치를 합리적으로 정해야 한다. 주어진 조건을 보면 별이 최대 100개 까지밖에 없으므로 이를 활용하여 생각해본다.&lt;/p&gt;
&lt;p&gt;우선 별 하나를 기준으로 보면 L * L 크기의 트램펄린이고, 별이 최대 100개 있으므로 확인해야 할 위치는 최악의 경우에 100,000,000,000,000개 이다. 사실상 위의 경우와 다를바가 없으므로 불가능하다.&lt;/p&gt;</description></item></channel></rss>