feat: remove duplicated gcd-like functions

Author: vil02

Diff for: Maths/GetEuclidGCD.js

@@ -1,13 +1,17 @@
+function CheckInput(a, b) {
+  if (typeof a !== 'number' || typeof b !== 'number') {
+    throw new TypeError('Arguments must be numbers')
+  }
+}
+
 /**
  * GetEuclidGCD Euclidean algorithm to determine the GCD of two numbers
  * @param {Number} a integer (may be negative)
  * @param {Number} b integer (may be negative)
  * @returns {Number} Greatest Common Divisor gcd(a, b)
  */
 export function GetEuclidGCD(a, b) {
-  if (typeof a !== 'number' || typeof b !== 'number') {
-    throw new TypeError('Arguments must be numbers')
-  }
+  CheckInput(a, b)
   a = Math.abs(a)
   b = Math.abs(b)
   while (b !== 0) {
@@ -17,3 +21,19 @@ export function GetEuclidGCD(a, b) {
   }
   return a
 }
+
+/**
+ * Recursive version of GetEuclidGCD
+ * @param {Number} a integer (may be negative)
+ * @param {Number} b integer (may be negative)
+ * @returns {Number} Greatest Common Divisor gcd(a, b)
+ */
+export function GetEuclidGCDRecursive(a, b) {
+  CheckInput(a, b)
+  a = Math.abs(a)
+  b = Math.abs(b)
+  if (b == 0) {
+    return a
+  }
+  return GetEuclidGCDRecursive(b, a % b)
+}

Diff for: Maths/test/GetEuclidGCD.test.js

@@ -1,22 +1,25 @@
-import { GetEuclidGCD } from '../GetEuclidGCD'
+import { GetEuclidGCD, GetEuclidGCDRecursive } from '../GetEuclidGCD'
 
-describe('GetEuclidGCD', () => {
-  it.each([
-    [5, 20, 5],
-    [109, 902, 1],
-    [290, 780, 10],
-    [104, 156, 52],
-    [0, 100, 100],
-    [-5, 50, 5],
-    [0, 0, 0],
-    [1, 1234567, 1]
-  ])('returns correct result for %i and %j', (inputA, inputB, expected) => {
-    expect(GetEuclidGCD(inputA, inputB)).toBe(expected)
-    expect(GetEuclidGCD(inputB, inputA)).toBe(expected)
-  })
+describe.each([GetEuclidGCD, GetEuclidGCDRecursive])(
+  '%# GetEuclidGCD',
+  (gcdFunction) => {
+    it.each([
+      [5, 20, 5],
+      [109, 902, 1],
+      [290, 780, 10],
+      [104, 156, 52],
+      [0, 100, 100],
+      [-5, 50, 5],
+      [0, 0, 0],
+      [1, 1234567, 1]
+    ])('returns correct result for %i and %j', (inputA, inputB, expected) => {
+      expect(gcdFunction(inputA, inputB)).toBe(expected)
+      expect(gcdFunction(inputB, inputA)).toBe(expected)
+    })
 
-  it('should throw when any of the inputs is not a number', () => {
-    expect(() => GetEuclidGCD('1', 2)).toThrowError()
-    expect(() => GetEuclidGCD(1, '2')).toThrowError()
-  })
-})
+    it('should throw when any of the inputs is not a number', () => {
+      expect(() => gcdFunction('1', 2)).toThrowError()
+      expect(() => gcdFunction(1, '2')).toThrowError()
+    })
+  }
+)