Files
JavaScript/String/AlphaNumericPalindrome.js
Roland Hummel 86d333ee94 feat: Test running overhaul, switch to Prettier & reformat everything (#1407)
* chore: Switch to Node 20 + Vitest

* chore: migrate to vitest mock functions

* chore: code style (switch to prettier)

* test: re-enable long-running test

Seems the switch to Node 20 and Vitest has vastly improved the code's and / or the test's runtime!

see #1193

* chore: code style

* chore: fix failing tests

* Updated Documentation in README.md

* Update contribution guidelines to state usage of Prettier

* fix: set prettier printWidth back to 80

* chore: apply updated code style automatically

* fix: set prettier line endings to lf again

* chore: apply updated code style automatically

---------

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Co-authored-by: Lars Müller <34514239+appgurueu@users.noreply.github.com>
2023-10-04 02:38:19 +05:30

37 lines
1.3 KiB
JavaScript

/**
* @function alphaNumericPalindrome
* @description alphaNumericPalindrome should return true if the string has alphanumeric characters that are palindrome irrespective of special characters and the letter case.
* @param {string} str the string to check
* @returns {boolean}
* @see [Palindrome](https://en.wikipedia.org/wiki/Palindrome)
* @example
* The function alphaNumericPalindrome() receives a string with varying formats
* like "racecar", "RaceCar", and "race CAR"
* The string can also have special characters
* like "2A3*3a2", "2A3 3a2", and "2_A3*3#A2"
*
* But the catch is, we have to check only if the alphanumeric characters
* are palindrome i.e remove spaces, symbols, punctuations etc
* and the case of the characters doesn't matter
*/
const alphaNumericPalindrome = (str) => {
if (typeof str !== 'string') {
throw new TypeError('Argument should be string')
}
// removing all the special characters and turning everything to lowercase
const newStr = str.replace(/[^a-z0-9]+/gi, '').toLowerCase()
const midIndex = newStr.length >> 1 // x >> y = floor(x / 2^y)
for (let i = 0; i < midIndex; i++) {
if (newStr.at(i) !== newStr.at(~i)) {
// ~n = -(n + 1)
return false
}
}
return true
}
export default alphaNumericPalindrome