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

JavaScript Basic: Exercise-83 with Solution

Find Longest String in Array

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

Visual Presentation:

Sample Solution:

JavaScript Code:

// Function to find the longest string(s) in an array
function longest_string(str_ara) {
  var max = str_ara[0].length; // Initialize max length with the length of the first string
  str_ara.map(v => max = Math.max(max, v.length)); // Update max with the maximum length in the array using the map function
  result = str_ara.filter(v => v.length == max); // Filter out strings that have the maximum length
  return result; // Return the array of longest strings
}	

// Example usage
console.log(longest_string(['a', 'aa', 'aaa', 'aaaaa', 'aaaa']));  

Output:

["aaaaa"]

Live Demo:

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

Flowchart:

ES6 Version:

// ES6 version with comments

// Function to find the longest strings in an array
const longest_string = (str_ara) => {
    let max = str_ara[0].length; // Initialize max length with the length of the first string
    str_ara.map(v => max = Math.max(max, v.length)); // Update max by finding the maximum length in the array
    result = str_ara.filter(v => v.length == max); // Filter strings that have the maximum length
    return result; // Return the result array
};

// Example usage
console.log(longest_string(['a', 'aa', 'aaa', 'aaaaa', 'aaaa']));

For more Practice: Solve these Related Problems:

• Write a JavaScript program that iterates through an array of strings and returns the longest one, handling ties by choosing the first occurrence.
• Write a JavaScript function that uses the reduce() method to find and return the longest string in an array.
• Write a JavaScript program that checks an array of strings for the one with maximum length and outputs it, accounting for empty arrays.

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