feat: find the vowels algorithm

Author: francislagares

src/algorithms/vowels/tests/vowels.test.ts

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+import { describe, test } from 'vitest';
+import { vowels, vowelsWithRegex } from '../vowels';
+
+describe('Finding Vowels', () => {
+  test('Vowels is a function', () => {
+    expect(typeof vowels).toEqual('function');
+    expect(typeof vowelsWithRegex).toEqual('function');
+  });
+
+  test('returns the number of vowels used', () => {
+    expect(vowels('aeiou')).toEqual(5);
+    expect(vowels('abcdefghijklmnopqrstuvwxyz')).toEqual(5);
+    expect(vowels('bcdfghjkl')).toEqual(0);
+  });
+
+  test('returns with recursion the number of vowels used', () => {
+    expect(vowelsWithRegex('aeiou')).toEqual(5);
+    expect(vowelsWithRegex('abcdefghijklmnopqrstuvwxyz')).toEqual(5);
+    expect(vowelsWithRegex('bcdfghjkl')).toEqual(0);
+  });
+});

src/algorithms/vowels/vowels.ts

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+// Option 1
+export const vowels = (str: string) => {
+  let count = 0;
+  const checker = ['a', 'e', 'i', 'o', 'u'];
+
+  for (const char of str.toLowerCase()) {
+    if (checker.includes(char)) {
+      count++;
+    }
+  }
+
+  return count;
+};
+
+// Option 2
+export const vowelsWithRegex = (str: string) => {
+  const matches = str.match(/[aeiou]/gi);
+  return matches ? matches.length : 0;
+};