JavaScript: Take any number of iterable objects or objects with a length property and returns the longest one

JavaScript fundamental (ES6 Syntax): Exercise-79 with Solution

Write a JavaScript program to take any number of iterable objects or objects with a length property and return the longest one.

• Use Array.prototype.reduce(), comparing the length of objects to find the longest one.
• If multiple objects have the same length, the first one will be returned.
• Returns undefined if no arguments are provided.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const longestItem = (...vals) => [...vals].sort((a, b) => b.length - a.length)[0];
console.log(longestItem('this', 'is', 'a', 'testcase'));
console.log(longestItem(...['a', 'ab', 'abc']));
console.log(longestItem(...['a', 'ab', 'abc'], 'abcd'));
console.log(longestItem([1, 2, 3], [1, 2], [1, 2, 3, 4, 5]));
console.log(longestItem([1, 2, 3], 'foobar'));

Sample Output:

testcase
abc
abcd
[1,2,3,4,5]
foobar

Pictorial Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-79-1 by w3resource (@w3resource) on CodePen.

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