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# Learn Python #3 — comprehensions
catalogue = [
    {"title": "Intro to Python", "views": 197},
    {"title": "Python Loops",    "views": 381},
    {"title": "Racket Install",  "views": 696},
]
 
popular = [v["title"] for v in catalogue if v["views"] > 200]
total   = sum(v["views"] for v in catalogue)
 
print(f"{len(popular)} hits out of {len(catalogue)}")
print(f"{total} lessons watched. Your turn.")

# Intro to Ruby — blocks and iterators
LESSONS = %w[python php ruby csharp racket].freeze
 
LESSONS.each_with_index do |track, i|
  puts format("%02d  %-8s ready", i + 1, track)
end
 
shipped = LESSONS.map(&:capitalize)
             .select { |name| name.length > 3 }
 
puts "Tracks live: #{shipped.join(', ')}"

<?php
declare(strict_types=1);
 
function e(string $value): string {
    return htmlspecialchars($value, ENT_QUOTES, 'UTF-8');
}
 
$name = trim($_POST['name'] ?? 'world');
?>
<h1>Hello, <?= e($name) ?>!</h1>
<p>Served by your own machine. Lesson 1 done.</p>