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JavaScript: Find the longest string from a given array of strings

JavaScript Basic: Exercise-83 with Solution

Write a JavaScript to find the longest string from a given array of strings.

Pictorial Presentation:

JavaScript: Find the longest string from a given array of strings.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JavaScript to find the longest string from a given array of strings</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function longest_string(str_ara) {
  var max = str_ara[0].length;
  str_ara.map(v => max = Math.max(max, v.length));
  result = str_ara.filter(v => v.length == max);
  return result;
}

console.log(longest_string(['a', 'aa', 'aaa',
                                          'aaaaa','aaaa']))

Sample Output:

["aaaaa"]

Flowchart:

Flowchart: JavaScript - Find the longest string from a given array of strings

ES6 Version:

function longest_string(str_ara) {
  let max = str_ara[0].length;
  str_ara.map(v => max = Math.max(max, v.length));
  result = str_ara.filter(v => v.length == max);
  return result;
}

console.log(longest_string(['a', 'aa', 'aaa',
                                          'aaaaa','aaaa']))

Live Demo:

See the Pen javascript-basic-exercise-83 by w3resource (@w3resource) on CodePen.



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Next: Write a JavaScript to replace each character of a given string by the next one in the English alphabet.

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JavaScript: Tips of the Day

Parameter's value

function getItems(fruitList, ...args, favoriteFruit) {
  return [...fruitList, ...args, favoriteFruit]
}

getItems(["banana", "apple"], "pear", "orange")

...args is a rest parameter. The rest parameter's value is an array containing all remaining arguments, and can only be the last parameter! In this example, the rest parameter was the second parameter. This is not possible, and will throw a syntax error.

function getItems(fruitList, favoriteFruit, ...args) {
  return [...fruitList, ...args, favoriteFruit];
}


getItems(['banana', 'apple'], 'pear', 'orange');
The above example works. This returns the array [ 'banana', 'apple', 'orange', 'pear' ].

Ref: https://bit.ly/3jFRBje