JavaScript: Check exceeding word

JavaScript String: Exercise-52 with Solution

There is an increasing gap between two adjacent characters in exceeding words. In ASCII, the gap represents the distance between two characters.
Write a JavaScript program to determine if a given word is exceeding word or not.
Adjacent characters:
'ac' -> 2
'cg' -> 4
'gl' -> 5
So 'acgl' is exceeding word.
Adjacent characters:
'ae' -> 4
'eb' -> 3
'bc' -> 1
So 'aebc' is not an exceeding word.
Test Data:
'acgl' -> true
'aebc' -> false

Sample Solution:

JavaScript Code:

 * Source: shorturl.at/asFM4
 * @function test
 * @param {string} text
 * @returns {boolean}
const test = (word) => {
    // Check if the input is a string
    if (typeof word !== 'string') {
        return 'It must be string';

    // Convert the word to uppercase and remove non-alphabetic characters
    const upperChars = word.toUpperCase().replace(/[^A-Z]/g, '');

    // Initialize an array to store the differences between adjacent characters
    const adjacentDiffList = [];

    // Iterate through the characters of the word
    for (let i = 0; i < upperChars.length - 1; i++) {
        // Get the current character and the adjacent character
        const { [i]: char, [i + 1]: adjacentChar } = upperChars;

        // Calculate the difference in ASCII values between adjacent characters
        if (char !== adjacentChar) {
                Math.abs(char.charCodeAt() - adjacentChar.charCodeAt())

    // Check if the adjacent differences are in non-decreasing order
    for (let i = 0; i < adjacentDiffList.length - 1; i++) {
        const { [i]: charDiff, [i + 1]: secondCharDiff } = adjacentDiffList;

        // If the adjacent differences are not in non-decreasing order, return false
        if (charDiff > secondCharDiff) {
            return false;
    // If all adjacent differences are in non-decreasing order, return true
    return true;

// Test cases
console.log(test('acgl'));   // Output: true
console.log(test('aebc'));   // Output: false
console.log(test(12356));    // Output: "It must be string"


It must be a string.


In the exercise above,

  • The function "test()" takes a single parameter 'word', which is expected to be a string.
  • It first checks if the input 'word' is indeed a string. If not, it returns the message "It must be a string".
  • The function then converts the input string to uppercase and removes all non-alphabetic characters using a regular expression.
  • It iterates through the characters of the modified string and calculates the absolute differences in ASCII values between adjacent characters. These differences are stored in the 'adjacentDiffList' array.
  • After calculating the differences, the function checks if the adjacent differences are in non-decreasing order. If any adjacent difference is greater than the next one, it returns 'false', indicating that the order is not non-decreasing.
  • If all adjacent differences are in non-decreasing order, the function returns 'true', indicating that the condition is met.


Flowchart: JavaScript: check exceeding word

Live Demo:

See the Pen javascript-string-exercise-52 by w3resource (@w3resource) on CodePen.

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