Arrays & Iterables
Count Array Items by Iteratee
easyJS SpecificJS / TS3 tests
Problem Statement
Implement `countBy(array, iteratee)` that groups array elements according to the result of `iteratee` and returns an object with the count of items in each group.
Examples
Example 1:
countBy([6.1, 4.2, 6.3], Math.floor); // { '4': 1, '6': 2 }
Example 2:
countBy(['one', 'two', 'three'], 'length'); // { '3': 2, '5': 1 }JavaScript & TypeScript starter code included
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