mirror of
https://github.com/TheAlgorithms/JavaScript.git
synced 2025-07-05 08:16:50 +08:00
merge: Upgrade max char (#983)
* feat: improved memoize function used Map instead of object & used the JSON.stringfy method for generate a valid string as a key * docs: modified documentation * style: format with standard * docs: modified stringify doc * refactor: remove two repetition implementation * feat: added validation, test codes * chore: remove useless words * feat: added types for jest * chore: added link box * feat: added new validation test casses & methods * style: formated with standard * feat: added parse method & test cases * docs: added js docs * chore: added default import export * feat: imporved algorithm via replace method * test: added two test cases * feat: added jest type for suggestions * feat: added `reduceRight` & `trim` method * chore: added helper variable * feat: added new rotation option * Revert "chore: added helper variable" This reverts commit 489544da0a3d479910fbea020d3be3d0d10681bf. * remove: yarn lock * chore: fix grammer * feat: used replace method & added test case * feat: remove revert * chore: added new line * feat: added filter for alphabets only * resolve: added empty validation improved ignore pattern * chore: reverted to for of loop
This commit is contained in:
@ -1,29 +1,36 @@
|
||||
/*
|
||||
Given a string of characters, return the character that appears the most often.
|
||||
Example: input = "Hello World!" return "l"
|
||||
*/
|
||||
const maxCharacter = (value) => {
|
||||
if (typeof value !== 'string') {
|
||||
throw new TypeError('The param should be a string')
|
||||
} else if (!value) {
|
||||
throw new Error('The param should be a valid string')
|
||||
/**
|
||||
* @function maxCharacter
|
||||
* @example - Given a string of characters, return the character that appears the most often. Example: input = "Hello World!" return "l"
|
||||
* @param {string} str
|
||||
* @param {RegExp} ignorePattern - ignore the char in str that is not required
|
||||
* @returns {string} - char
|
||||
*/
|
||||
const maxCharacter = (str, ignorePattern) => { // initially it's count only alphabets
|
||||
if (typeof str !== 'string') {
|
||||
throw new TypeError('Argument should be a string')
|
||||
} else if (!str) {
|
||||
throw new Error('The param should be a nonempty string')
|
||||
}
|
||||
|
||||
const occurrences = {}
|
||||
for (let i = 0; i < value.length; i++) {
|
||||
const char = value[i]
|
||||
if (/\s/.test(char)) continue
|
||||
occurrences[char] = occurrences[char] + 1 || 1
|
||||
}
|
||||
let maxCharacter = null
|
||||
let maxCount = 0
|
||||
Object.keys(occurrences).forEach(char => {
|
||||
if (occurrences[char] > maxCount) {
|
||||
maxCount = occurrences[char]
|
||||
maxCharacter = char
|
||||
// store all char in occurrence map
|
||||
const occurrenceMap = new Map()
|
||||
|
||||
for (const char of str) {
|
||||
if (!ignorePattern?.test(char)) {
|
||||
occurrenceMap.set(char, occurrenceMap.get(char) + 1 || 1)
|
||||
}
|
||||
})
|
||||
return maxCharacter
|
||||
}
|
||||
|
||||
// find the max char from the occurrence map
|
||||
let max = { char: '', occur: -Infinity }
|
||||
|
||||
for (const [char, occur] of occurrenceMap) {
|
||||
if (occur > max.occur) {
|
||||
max = { char, occur }
|
||||
}
|
||||
}
|
||||
|
||||
return max.char
|
||||
}
|
||||
|
||||
export { maxCharacter }
|
||||
export default maxCharacter
|
||||
|
@ -1,12 +1,21 @@
|
||||
import { maxCharacter } from '../MaxCharacter'
|
||||
import maxCharacter from '../MaxCharacter'
|
||||
|
||||
describe('Testing the maxCharacter function', () => {
|
||||
it('Expect throw with wrong arg', () => {
|
||||
expect(() => maxCharacter(123)).toThrow()
|
||||
expect(() => maxCharacter('')).toThrow()
|
||||
})
|
||||
|
||||
it('Check the max character in string', () => {
|
||||
const theString = 'I can\'t do that'
|
||||
const maxChar = maxCharacter(theString)
|
||||
const maxCharInAllCount = maxCharacter(theString)
|
||||
const maxChar = maxCharacter(theString, /\s/)
|
||||
|
||||
expect(maxCharInAllCount).toBe(' ')
|
||||
expect(maxChar).toBe('t')
|
||||
|
||||
expect(maxCharacter('!!!Hello, World!!!', /[a-z]/)).toBe('!')
|
||||
|
||||
expect(maxCharacter('!!!Hello, World!!!', /[^a-z]/i)).toBe('l')
|
||||
})
|
||||
})
|
||||
|
Reference in New Issue
Block a user