import { factorial, permutation, combination } from '../PermutationAndCombination' describe('Factorial', () => { it('factorial(5)', () => { expect(factorial(5)).toBe(120) }) }) describe('Permutation', () => { it('permutation(5, 2)', () => { expect(permutation(5, 2)).toBe(20) }) }) describe('Combination', () => { it('combination(5, 2)', () => { expect(combination(5, 2)).toBe(10) }) })