diff --git a/String/AlphaNumericPalindrome.js b/String/AlphaNumericPalindrome.js new file mode 100644 index 000000000..2d1a071a2 --- /dev/null +++ b/String/AlphaNumericPalindrome.js @@ -0,0 +1,56 @@ +/** + * alphaNumericPlaindrome 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` + */ + +/***************************************************************************** + * What is a palindrome? https://en.wikipedia.org/wiki/Palindrome + * + * The function alphaNumericPlaindrome() recieves a sting 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 + * + * This is one of the questions/projects that we have to solve for the + * JavaScript Algorithms and Data Structures course on https://www.freecodecamp.org + * + * Author -- Syed Fasiuddin + * https://github.com/SyedFasiuddin + * + ****************************************************************************/ + +const alphaNumericPlaindrome = (str) => { + // removing all the special characters and turning everything to lowercase + const newStr = str.replace(/[^a-zA-Z0-9]*/g, '').toLowerCase() + // the newStr variable is a string and only has alphanumeric characters all in lowercase + + // making an array of individual characters as it's elements + const arr = newStr.split('') + + // setting a variable to see if change occurs to it + let palin = 0 + + // making a copy of arr with spread operator + const arrRev = [...arr] + // you can use arrRev.reverse() to reverse the array + // or else you can use the below method + + // iterate through the arr and check the condition of palindrome + for (let i = 0; i < arr.length; i++) { + if (arr[i] !== arrRev[arr.length - 1 - i]) { + // if the string is not palindrome then we change palin varaible to 1 + palin = 1 + } + } + + // if the string is palindrome then palin variable is never changed + if (palin === 0) return true + else return false +} + +export { alphaNumericPlaindrome } diff --git a/String/test/AlphaNumericPalindrome.test.js b/String/test/AlphaNumericPalindrome.test.js new file mode 100644 index 000000000..f544c565b --- /dev/null +++ b/String/test/AlphaNumericPalindrome.test.js @@ -0,0 +1,21 @@ +import { alphaNumericPlaindrome } from '../AlphaNumericPalindrome' + +test('should return true if the given string has alphanumeric characters that are palindrom irrespective of case and symbols', () => { + expect(alphaNumericPlaindrome('eye')).toBe(true) +}) + +test('should return true if the given string has alphanumeric characters that are palindrom irrespective of case and symbols', () => { + expect(alphaNumericPlaindrome('0_0 (: /-:) 0-0')).toBe(true) +}) + +test('should return true if the given string has alphanumeric characters that are palindrom irrespective of case and symbols', () => { + expect(alphaNumericPlaindrome('five|_/|four')).toBe(false) +}) + +test('should return true if the given string has alphanumeric characters that are palindrom irrespective of case and symbols', () => { + expect(alphaNumericPlaindrome('A man, a plan, a canal. Panama')).toBe(true) +}) + +test('should return true if the given string has alphanumeric characters that are palindrom irrespective of case and symbols', () => { + expect(alphaNumericPlaindrome('1 eye for of 1 eye.')).toBe(false) +})