Skip to content
Open
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension


Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
36 changes: 36 additions & 0 deletions Maths/LCM.js
Original file line number Diff line number Diff line change
@@ -0,0 +1,36 @@
/**
* @function lcm
* @description Compute the least common multiple (LCM) of two integers.
* @param {number} a - first integer
* @param {number} b - second integer
* @return {number} LCM of a and b
* @example lcm(4,6) -> 12
* @example lcm(7,3) -> 21
*/
const gcd = (x, y) => {
let a = Math.abs(x)
let b = Math.abs(y)
if (Number.isNaN(a) || Number.isNaN(b)) throw new TypeError('Argument is NaN - Not a Number')
while (b !== 0) {
const t = a % b
a = b
b = t
}
return a
}

const lcm = (a, b) => {
const na = Number(a)
const nb = Number(b)

if (Number.isNaN(na) || Number.isNaN(nb) || typeof a === 'object' || typeof b === 'object') {
throw new TypeError('Argument is NaN - Not a Number')
}

if (na === 0 || nb === 0) return 0

// lcm(a,b) = |a * b| / gcd(a,b)
return Math.abs((na / gcd(na, nb)) * nb)
}

export { lcm }
28 changes: 28 additions & 0 deletions Maths/test/LCM.test.js
Original file line number Diff line number Diff line change
@@ -0,0 +1,28 @@
import { describe, it, expect } from 'vitest'
import { lcm } from '../LCM'

describe('lcm()', () => {
it('returns 0 when either argument is 0', () => {
expect(lcm(0, 5)).toBe(0)
expect(lcm(7, 0)).toBe(0)
})

it('computes LCM for positive integers', () => {
expect(lcm(4, 6)).toBe(12)
expect(lcm(7, 3)).toBe(21)
expect(lcm(21, 6)).toBe(42)
})

it('computes LCM when inputs are negative', () => {
expect(lcm(-4, 6)).toBe(12)
expect(lcm(4, -6)).toBe(12)
expect(lcm(-4, -6)).toBe(12)
})

it('throws for non-numeric inputs', () => {
// @ts-ignore
expect(() => lcm('a', 5)).toThrow()
// @ts-ignore
expect(() => lcm(4, {})).toThrow()
})
})
4 changes: 2 additions & 2 deletions package.json
Original file line number Diff line number Diff line change
Expand Up @@ -13,11 +13,11 @@
"author": "TheAlgorithms",
"license": "GPL-3.0",
"devDependencies": {
"@vitest/coverage-v8": "^1.2.1",
"globby": "^13.2.2",
"husky": "^8.0.3",
"prettier": "^3.0.3",
"vitest": "^1.2.1",
"@vitest/coverage-v8": "^1.2.1"
"vitest": "^3.2.4"
},
"engines": {
"node": ">=20.6.0"
Expand Down
Loading