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sudo sed -i -e "s|mirrorlist=|#mirrorlist=|g" /etc/yum.repos.d/CentOS-*
sudo sed -i -e "s|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g" /etc/yum.repos.d/CentOS-*

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var collator = new RuleBasedCollator("< b < a");

var strings = List.of("aaa", "bbb", "ccc", "aba");

var sortedStrings = strings.stream()
                .sorted(collator::compare)
                .toList();

System.out.println(sortedStrings);

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var strings = List.of("aaa", "bbb", "ddd", "ccc", "aba");

var sortedStrings = strings.stream().sorted().toList();

System.out.println(sortedStrings);

// => [aaa, aba, bbb, ccc, ddd]

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concat = foldr mappend empty

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getSum ( Sum 1 `mappend` Sum 2 ) -- this returns 3

getProduct ( Product 5 `mappend` Product 10 ) -- this returns 50

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instance Num a => Monoid (Product a) where
    mempty = Product 1
    Product x `mappend` Product y = Product (x * y)

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Product 1
Sum 3

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newtype Sum a = Sum { getSum :: a }

newtype Product a = Product { getProduct :: a }

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class Monoid m where
    mempty :: m
    mappend :: m -> m -> m

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data Person = Person { 
  name    :: String,
  surname :: String,
  age     :: Int 
}