Added new algoritm (#433)

Author: josecarlosweb

String/CheckVowels.js

@@ -0,0 +1,21 @@
+/*
+ Given a string of words or phrases, count the number of vowels.
+ Example: input = "hello world" return 3
+ */
+
+const checkVowels = (value) => {
+ if (typeof value !== 'string') {
+ throw new TypeError('The first param should be a string')
+ }
+ const vowels = ['a', 'e', 'i', 'o', 'u']
+ let countVowels = 0
+ for (let i = 0; i < value.length; i++) {
+ const char = value[i].toLowerCase()
+ if (vowels.includes(char)) {
+ countVowels++
+ }
+ }
+ return countVowels
+}
+
+export { checkVowels }

String/CheckVowels.test.js

@@ -0,0 +1,12 @@
+import { checkVowels } from './CheckVowels'
+
+describe('Test the checkVowels function', () => {
+ it('expect throws on use wrong param', () => {
+ expect(() => checkVowels(0)).toThrow()
+ })
+ it('count the vowels in a string', () => {
+ const value = 'Mad World'
+ const countVowels = checkVowels(value)
+ expect(countVowels).toBe(2)
+ })
+})