Course of Raku / Addendum 🆕 / Working with data / Lists, arrays, and hashes / Exercises / The most common element

Solution: The most common element

Here is a possible solution to the task.

Code

my @values = <a b a c a b>;

my %count;
%count{$_}++ for @values;

say %count.sort(-*.value)[0].key;

🦋 You can find the source code in the file most-common.raku.

Output

a

Comments

1. After tallying each value in %count, sorting the pairs by -*.value puts the most frequent first; [0].key then gives back that element.

2. Raku can do the tallying for you with a Bag, which counts how many times each value appears. Then .max(*.value) picks the pair with the highest count, and .key is the element itself:

   my @values = <a b a c a b>;
   
   say @values.Bag.max(*.value).key; # a

   The whole tally is a single method call, and there is no explicit hash to manage.

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