Fix/code smells

Bit-Manipulation/IsPowerOfTwo.js

@@ -23,8 +23,5 @@
 */
 
 export const IsPowerOfTwo = (n) => {
-  if (n > 0 && (n & (n - 1)) === 0) {
-    return true
-  }
-  return false
+  return n > 0 && (n & (n - 1)) === 0
 }

Cellular-Automata/ConwaysGameOfLife.js

@@ -29,11 +29,12 @@ export function newGeneration (cells) {
 
       // Decide whether the cell is alive or dead
       const alive = cells[i][j] === 1
-      if ((alive && neighbourCount >= 2 && neighbourCount <= 3) || (!alive && neighbourCount === 3)) {
-        nextGenerationRow.push(1)
-      } else {
-        nextGenerationRow.push(0)
-      }
+
+      const cellIsAlive =
+        (alive && neighbourCount >= 2 && neighbourCount <= 3) ||
+        (!alive && neighbourCount === 3)
+
+      nextGenerationRow.push(cellIsAlive ? 1 : 0)
     }
     nextGeneration.push(nextGenerationRow)
   }

Conversions/DateDayDifference.js

@@ -19,7 +19,7 @@ const DateToDay = (dd, mm, yyyy) => {
 
 const DateDayDifference = (date1, date2) => {
   // firstly, check that both input are string or not.
-  if (typeof date1 !== 'string' && typeof date2 !== 'string') {
+  if (typeof date1 !== 'string' || typeof date2 !== 'string') {
     return new TypeError('Argument is not a string.')
   }
   // extract the first date

DIRECTORY.md

@@ -1,5 +1,6 @@
 * **Backtracking**
   * [AllCombinationsOfSizeK](Backtracking/AllCombinationsOfSizeK.js)
+  * [generateParentheses](Backtracking/generateParentheses.js)
   * [GeneratePermutations](Backtracking/GeneratePermutations.js)
   * [KnightTour](Backtracking/KnightTour.js)
   * [NQueens](Backtracking/NQueens.js)
@@ -18,12 +19,14 @@
   * [Memoize](Cache/Memoize.js)
 * **Cellular-Automata**
   * [ConwaysGameOfLife](Cellular-Automata/ConwaysGameOfLife.js)
+  * [Elementary](Cellular-Automata/Elementary.js)
 * **Ciphers**
   * [AffineCipher](Ciphers/AffineCipher.js)
   * [Atbash](Ciphers/Atbash.js)
   * [CaesarCipher](Ciphers/CaesarCipher.js)
   * [KeyFinder](Ciphers/KeyFinder.js)
   * [KeywordShiftedAlphabet](Ciphers/KeywordShiftedAlphabet.js)
+  * [MorseCode](Ciphers/MorseCode.js)
   * [ROT13](Ciphers/ROT13.js)
   * [VigenereCipher](Ciphers/VigenereCipher.js)
   * [XORCipher](Ciphers/XORCipher.js)
@@ -66,6 +69,7 @@
     * [Graph2](Data-Structures/Graph/Graph2.js)
     * [Graph3](Data-Structures/Graph/Graph3.js)
   * **Heap**
+    * [KeyPriorityQueue](Data-Structures/Heap/KeyPriorityQueue.js)
     * [MaxHeap](Data-Structures/Heap/MaxHeap.js)
     * [MinHeap](Data-Structures/Heap/MinHeap.js)
     * [MinPriorityQueue](Data-Structures/Heap/MinPriorityQueue.js)
@@ -112,7 +116,10 @@
   * [Shuf](Dynamic-Programming/Shuf.js)
   * [SieveOfEratosthenes](Dynamic-Programming/SieveOfEratosthenes.js)
   * **Sliding-Window**
+    * [HouseRobber](Dynamic-Programming/Sliding-Window/HouseRobber.js)
     * [LongestSubstringWithoutRepeatingCharacters](Dynamic-Programming/Sliding-Window/LongestSubstringWithoutRepeatingCharacters.js)
+    * [MaxConsecutiveOnes](Dynamic-Programming/Sliding-Window/MaxConsecutiveOnes.js)
+    * [MaxConsecutiveOnesIII](Dynamic-Programming/Sliding-Window/MaxConsecutiveOnesIII.js)
     * [PermutationinString](Dynamic-Programming/Sliding-Window/PermutationinString.js)
   * [SudokuSolver](Dynamic-Programming/SudokuSolver.js)
   * [TrappingRainWater](Dynamic-Programming/TrappingRainWater.js)
@@ -212,6 +219,7 @@
   * [ModularBinaryExponentiationRecursive](Maths/ModularBinaryExponentiationRecursive.js)
   * [NumberOfDigits](Maths/NumberOfDigits.js)
   * [Palindrome](Maths/Palindrome.js)
+  * [ParityOutlier](Maths/ParityOutlier.js)
   * [PascalTriangle](Maths/PascalTriangle.js)
   * [PerfectCube](Maths/PerfectCube.js)
   * [PerfectNumber](Maths/PerfectNumber.js)
@@ -365,7 +373,6 @@
   * [Upper](String/Upper.js)
   * [ValidateCreditCard](String/ValidateCreditCard.js)
   * [ValidateEmail](String/ValidateEmail.js)
-  * [ValidateUrl](String/ValidateUrl.js)
   * [ZFunction](String/ZFunction.js)
 * **Timing-Functions**
   * [GetMonthDays](Timing-Functions/GetMonthDays.js)

Data-Structures/Graph/test/Graph2.test.js

@@ -5,9 +5,7 @@ describe('Test Graph2', () => {
   const graph = new Graph(vertices.length)
 
   // adding vertices
-  for (let i = 0; i < vertices.length; i++) {
-    graph.addVertex(vertices[i])
-  }
+  vertices.forEach((vertice) => graph.addVertex(vertice))
 
   // adding edges
   graph.addEdge('A', 'B')
@@ -27,7 +25,7 @@ describe('Test Graph2', () => {
     expect(mockFn.mock.calls.length).toBe(vertices.length)
 
     // Collect adjacency lists from output (call args)
-    const adjListArr = mockFn.mock.calls.map(v => v[0])
+    const adjListArr = mockFn.mock.calls.map((v) => v[0])
 
     expect(adjListArr).toEqual([
       'A -> B D E ',

Data-Structures/Heap/MinPriorityQueue.js

@@ -47,8 +47,7 @@ class MinPriorityQueue {
 
   // returns boolean value whether the heap is full or not
   isFull () {
-    if (this.size === this.capacity) return true
-    return false
+    return this.size === this.capacity
   }
 
   // prints the heap

Data-Structures/Tree/Trie.js

@@ -106,8 +106,8 @@ Trie.prototype.contains = function (word) {
   // find the node with given prefix
   const node = this.findPrefix(word)
   // No such word exists
-  if (node === null || node.count === 0) return false
-  return true
+
+  return node !== null && node.count !== 0
 }
 
 Trie.prototype.findOccurrences = function (word) {

Dynamic-Programming/FindMonthCalendar.js

@@ -3,6 +3,7 @@
 *  And prints out the month's calendar.
 *  It uses an epoch of 1/1/1900, Monday.
 */
+import { isLeapYear } from '../Maths/LeapYear'
 
 class Month {
   constructor () {
@@ -51,11 +52,6 @@ class Month {
     return dateOb
   }
 
-  isLeapYear (year) {
-    if (((year % 400) === 0) || (((year % 100) !== 0) && ((year % 4) === 0))) return true
-    return false
-  }
-
   isGreater (startDate, endDate) {
     if (startDate.year > endDate.year) {
       return true
@@ -79,16 +75,16 @@ class Month {
     }
     let diff = 0
     while (startDate.year !== endDate.year) {
-      diff += (this.isLeapYear(startDate.year)) ? 366 : 365
+      diff += (isLeapYear(startDate.year)) ? 366 : 365
       startDate.year = startDate.year + 1
     }
     while (startDate.month !== endDate.month) {
       if (startDate.month < endDate.month) {
-        if (this.isLeapYear(startDate.year)) diff += this.monthDaysLeap[startDate.month]
+        if (isLeapYear(startDate.year)) diff += this.monthDaysLeap[startDate.month]
         else diff += this.monthDays[startDate.month]
         startDate.month = startDate.month + 1
       } else {
-        if (this.isLeapYear(startDate.year)) diff -= this.monthDaysLeap[startDate.month - 1]
+        if (isLeapYear(startDate.year)) diff -= this.monthDaysLeap[startDate.month - 1]
         else diff -= this.monthDays[startDate.month - 1]
         startDate.month = startDate.month - 1
       }
@@ -103,7 +99,7 @@ class Month {
     let Month2 = this.parseDate(date)
     day = (this.isGreater(Month2, this.epoch)) ? this.Days[difference] : this.BDays[difference]
     Month2 = this.parseDate(date)
-    if (this.isLeapYear(Month2.year)) this.printCal(this.monthDaysLeap[Month2.month], day)
+    if (isLeapYear(Month2.year)) this.printCal(this.monthDaysLeap[Month2.month], day)
     else this.printCal(this.monthDays[Month2.month], day)
   }
 }

Graphs/DijkstraSmallestPath.js

@@ -41,70 +41,3 @@ function solve (graph, s) {
 }
 
 export { solve }
-
-// // create graph
-// const graph = {}
-
-// const layout = {
-//   R: ['2'],
-//   2: ['3', '4'],
-//   3: ['4', '6', '13'],
-//   4: ['5', '8'],
-//   5: ['7', '11'],
-//   6: ['13', '15'],
-//   7: ['10'],
-//   8: ['11', '13'],
-//   9: ['14'],
-//   10: [],
-//   11: ['12'],
-//   12: [],
-//   13: ['14'],
-//   14: [],
-//   15: []
-// }
-
-// // convert uni-directional to bi-directional graph
-// let  graph = {
-//     a: {e:1, b:1, g:3},
-//     b: {a:1, c:1},
-//     c: {b:1, d:1},
-//     d: {c:1, e:1},
-//     e: {d:1, a:1},
-//     f: {g:1, h:1},
-//     g: {a:3, f:1},
-//     h: {f:1}
-// };
-
-// for (const id in layout) {
-//   if (!graph[id]) { graph[id] = {} }
-//   layout[id].forEach(function (aid) {
-//     graph[id][aid] = 1
-//     if (!graph[aid]) { graph[aid] = {} }
-//     graph[aid][id] = 1
-//   })
-// }
-
-// // choose start node
-// const start = '10'
-// // get all solutions
-// const solutions = solve(graph, start)
-
-// // for s in solutions..
-// ' -> ' + s + ': [' + solutions[s].join(', ') + ']   (dist:' + solutions[s].dist + ')'
-
-// From '10' to
-//  -> 2: [7, 5, 4, 2]   (dist:4)
-//  -> 3: [7, 5, 4, 3]   (dist:4)
-//  -> 4: [7, 5, 4]   (dist:3)
-//  -> 5: [7, 5]   (dist:2)
-//  -> 6: [7, 5, 4, 3, 6]   (dist:5)
-//  -> 7: [7]   (dist:1)
-//  -> 8: [7, 5, 4, 8]   (dist:4)
-//  -> 9: [7, 5, 4, 3, 13, 14, 9]   (dist:7)
-//  -> 10: []   (dist:0)
-//  -> 11: [7, 5, 11]   (dist:3)
-//  -> 12: [7, 5, 11, 12]   (dist:4)
-//  -> 13: [7, 5, 4, 3, 13]   (dist:5)
-//  -> 14: [7, 5, 4, 3, 13, 14]   (dist:6)
-//  -> 15: [7, 5, 4, 3, 6, 15]   (dist:6)
-//  -> R: [7, 5, 4, 2, R]   (dist:5)

Maths/LeapYear.js

@@ -14,9 +14,5 @@
  * @returns {boolean} true if this is a leap year, false otherwise.
  */
 export const isLeapYear = (year) => {
-  if (year % 400 === 0) return true
-  if (year % 100 === 0) return false
-  if (year % 4 === 0) return true
-
-  return false
+  return ((year % 400) === 0) || (((year % 100) !== 0) && ((year % 4) === 0))
 }

Maths/MatrixMultiplication.js

@@ -20,12 +20,9 @@ const matrixCheck = (matrix) => {
 // tests to see if the matrices have a like side, i.e. the row length on the first matrix matches the column length on the second matrix, or vice versa.
 const twoMatricesCheck = (first, second) => {
   const [firstRowLength, secondRowLength, firstColLength, secondColLength] = [first.length, second.length, matrixCheck(first), matrixCheck(second)]
-  if (firstRowLength !== secondColLength || secondRowLength !== firstColLength) {
-    // These matrices do not have a common side
-    return false
-  } else {
-    return true
-  }
+
+  // These matrices do not have a common side
+  return firstRowLength === secondColLength && secondRowLength === firstColLength
 }
 
 // returns an empty array that has the same number of rows as the left matrix being multiplied.

Maths/MidpointIntegration.js

@@ -41,8 +41,7 @@ function integralEvaluation (N, a, b, func) {
 
   // Calculate the integral
   let result = h
-  temp = 0
-  for (let i = 0; i < pointsArray.length; i++) temp += pointsArray[i]
+  temp = pointsArray.reduce((acc, currValue) => acc + currValue, 0)
 
   result *= temp
 

Maths/SimpsonIntegration.js

@@ -54,8 +54,7 @@ function integralEvaluation (N, a, b, func) {
 
   // Calculate the integral
   let result = h / 3
-  temp = 0
-  for (let i = 0; i < pointsArray.length; i++) temp += pointsArray[i]
+  temp = pointsArray.reduce((acc, currValue) => acc + currValue, 0)
 
   result *= temp
 

String/CheckRearrangePalindrome.js

@@ -12,7 +12,7 @@ export const palindromeRearranging = (str) => {
     return 'Not a string'
   }
   // Check if is a empty string
-  if (str.length === 0) {
+  if (!str) {
     return 'Empty string'
   }