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+<title>Day 4 - Advent of Code 2017</title>
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+Oh, hello! Funny seeing you here.
+
+I appreciate your enthusiasm, but you aren't going to find much down here.
+There certainly aren't clues to any of the puzzles. The best surprises don't
+even appear in the source until you unlock them for real.
+
+Please be careful with automated requests; I'm not Google, and I can only take
+so much traffic. Please be considerate so that everyone gets to play.
+
+If you're curious about how Advent of Code works, it's running on some custom
+Perl code. Other than a few integrations (auth, analytics, ads, social media),
+I built the whole thing myself, including the design, animations, prose, and
+all of the puzzles.
+
+The puzzles probably took the longest; the easiest ones took an hour or two
+each, but the harder ones took 4-5 hours, and a few even longer than that. A
+lot of effort went into building this thing - I hope you're enjoying playing it
+as much as I enjoyed making it for you!
+
+If you'd like to hang out, I'm @ericwastl on Twitter.
+
+- Eric Wastl
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+-->
+<body>
+<header><div><h1 class="title-global"><a href="/">Advent of Code</a></h1><nav><ul><li><a href="/2017/about">[About]</a></li><li><a href="/2017/support">[AoC++]</a></li><li><a href="/2017/events">[Events]</a></li><li><a href="/2017/settings">[Settings]</a></li><li><a href="/2017/auth/logout">[Log Out]</a></li></ul></nav><div class="user">Neil Smith <span class="supporter">(AoC++)</span> <span class="star-count">12*</span></div></div><div><h1 class="title-event"> <span class="title-event-wrap">λy.</span><a href="/2017">2017</a><span class="title-event-wrap"></span></h1><nav><ul><li><a href="/2017">[Calendar]</a></li><li><a href="/2017/leaderboard">[Leaderboard]</a></li><li><a href="/2017/stats">[Stats]</a></li><li><a href="/2017/sponsors">[Sponsors]</a></li></ul></nav></div></header>
+
+<div id="sidebar">
+<div id="sponsor"><div class="quiet">Our <a href="/2017/sponsors">sponsors</a> help make Advent of Code possible:</div><p><a href="https://formlabs.com/" target="_blank" onclick="if(ga)ga('send','event','sponsor','click',this.href);" rel="noopener">Formlabs</a> - We make powerful, affordable 3D printers for professionals.</p></div>
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+
+<main>
+<article class="day-desc"><h2>--- Day 4: High-Entropy Passphrases ---</h2><p>A new system policy has been put in place that requires all accounts to use a <em>passphrase</em> instead of simply a pass<em>word</em>. A passphrase consists of a series of words (lowercase letters) separated by spaces.</p>
+<p>To ensure security, a valid passphrase must contain no duplicate words.</p>
+<p>For example:</p>
+<ul>
+<li><code>aa bb cc dd ee</code> is valid.</li>
+<li><code>aa bb cc dd aa</code> is not valid - the word <code>aa</code> appears more than once.</li>
+<li><code>aa bb cc dd aaa</code> is valid - <code>aa</code> and <code>aaa</code> count as different words.</li>
+</ul>
+<p>The system's full passphrase list is available as your puzzle input. <em>How many passphrases are valid?</em></p>
+</article>
+<p>Your puzzle answer was <code>383</code>.</p><article class="day-desc"><h2>--- Part Two ---</h2><p>For added security, <span title="Because as everyone knows, the number of rules is proportional to the level of security.">yet another system policy</span> has been put in place. Now, a valid passphrase must contain no two words that are anagrams of each other - that is, a passphrase is invalid if any word's letters can be rearranged to form any other word in the passphrase.</p>
+<p>For example:</p>
+<ul>
+<li><code>abcde fghij</code> is a valid passphrase.</li>
+<li><code>abcde xyz ecdab</code> is not valid - the letters from the third word can be rearranged to form the first word.</li>
+<li><code>a ab abc abd abf abj</code> is a valid passphrase, because <em>all</em> letters need to be used when forming another word.</li>
+<li><code>iiii oiii ooii oooi oooo</code> is valid.</li>
+<li><code>oiii ioii iioi iiio</code> is not valid - any of these words can be rearranged to form any other word.</li>
+</ul>
+<p>Under this new system policy, <em>how many passphrases are valid?</em></p>
+</article>
+<p>Your puzzle answer was <code>265</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
+<p>At this point, you should <a href="/2017">return to your advent calendar</a> and try another puzzle.</p>
+<p>If you still want to see it, you can <a href="4/input" target="_blank">get your puzzle input</a>.</p>
+<p>You can also <span class="share">[Share<span class="share-content">on
+ <a href="https://twitter.com/intent/tweet?text=I%27ve+completed+%22High%2DEntropy+Passphrases%22+%2D+Day+4+%2D+Advent+of+Code+2017&url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F4&related=ericwastl&hashtags=AdventOfCode" target="_blank">Twitter</a>
+ <a href="https://plus.google.com/share?url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F4" target="_blank">Google+</a>
+ <a href="http://www.reddit.com/submit?url=http%3A%2F%2Fadventofcode%2Ecom%2F2017%2Fday%2F4&title=I%27ve+completed+%22High%2DEntropy+Passphrases%22+%2D+Day+4+%2D+Advent+of+Code+2017" target="_blank">Reddit</a
+></span>]</span> this puzzle.</p>
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