Fix TheAlgorithms#748 : Revise algorithm implementation so that it actually returns the combinations. Fix test (was not running, .mjs not matching Jest pattern) and work.

Author: lvlte

Backtracking/AllCombinationsOfSizeK.js

@@ -25,19 +25,21 @@ class Combinations {
  constructor (n, k) {
  this.n = n
  this.k = k
- this.combinationArray = [] // will be used for storing current combination
+ this.current = [] // will be used for storing current combination
+ this.combinations = []
  }
 
  findCombinations (high = this.n, total = this.k, low = 1) {
  if (total === 0) {
- console.log(this.combinationArray)
- return
+ this.combinations.push([...this.current])
+ return this.combinations
  }
  for (let i = low; i <= high; i++) {
- this.combinationArray.push(i)
+ this.current.push(i)
  this.findCombinations(high, total - 1, i + 1)
- this.combinationArray.pop()
+ this.current.pop()
  }
+ return this.combinations
  }
 }
 

Backtracking/tests/AllCombinationsOfSizeK.test.mjs renamed to Backtracking/tests/AllCombinationsOfSizeK.test.js

@@ -3,11 +3,11 @@ import { Combinations } from '../AllCombinationsOfSizeK'
 describe('AllCombinationsOfSizeK', () => {
  it('should return 3x2 matrix solution for n = 3 and k = 2', () => {
  const test1 = new Combinations(3, 2)
- expect(test1.findCombinations).toEqual([[1, 2], [1, 3], [2, 3]])
+ expect(test1.findCombinations()).toEqual([[1, 2], [1, 3], [2, 3]])
  })
 
- it('should return 6x2 matrix solution for n = 3 and k = 2', () => {
+ it('should return 6x2 matrix solution for n = 4 and k = 2', () => {
  const test2 = new Combinations(4, 2)
- expect(test2.findCombinations).toEqual([[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]])
+ expect(test2.findCombinations()).toEqual([[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]])
  })
 })