feat: anagram algorithm

Author: francislagares

src/algorithms/anagrams/anagrams.ts

@@ -0,0 +1,36 @@
+// Option 1 ( the hard way )
+export const anagrams = (stringA: string, stringB: string) => {
+  const aCharMap = buildCharMap(stringA);
+  const bCharMap = buildCharMap(stringB);
+
+  if (Object.keys(aCharMap).length !== Object.keys(bCharMap).length) {
+    return false;
+  }
+
+  for (const char in aCharMap) {
+    if (aCharMap[char] !== bCharMap[char]) {
+      return false;
+    }
+  }
+
+  return true;
+};
+
+const buildCharMap = (str: string) => {
+  const charMap = {};
+
+  for (const char of str.replace(/[^\w]/g, '').toLowerCase()) {
+    charMap[char] = charMap[char] + 1 || 1;
+  }
+
+  return charMap;
+};
+
+// Option 2 ( easy way )
+export const easyAnagram = (stringA: string, stringB: string) => {
+  return cleanString(stringA) === cleanString(stringB);
+};
+
+const cleanString = str => {
+  return str.replace(/[^\w]/g, '').toLowerCase().split('').sort().join('');
+};

src/algorithms/anagrams/tests/anagrams.test.ts

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+import { anagrams, easyAnagram } from '../anagrams';
+import { describe, test } from 'vitest';
+
+describe('Anagrams Algorithm', () => {
+  test('anagrams function exists', () => {
+    expect(typeof anagrams).toEqual('function');
+    expect(typeof easyAnagram).toEqual('function');
+  });
+
+  test('"hello" is an anagram of "llohe"', () => {
+    expect(anagrams('hello', 'llohe')).toBeTruthy();
+    expect(easyAnagram('hello', 'llohe')).toBeTruthy();
+  });
+
+  test('"Whoa! Hi!" is an anagram of "Hi! Whoa!"', () => {
+    expect(anagrams('Whoa! Hi!', 'Hi! Whoa!')).toBeTruthy();
+    expect(easyAnagram('Whoa! Hi!', 'Hi! Whoa!')).toBeTruthy();
+  });
+
+  test('"One One" is not an anagram of "Two two two"', () => {
+    expect(anagrams('One One', 'Two two two')).toBeFalsy();
+    expect(easyAnagram('One One', 'Two two two')).toBeFalsy();
+  });
+
+  test('"One one" is not an anagram of "One one c"', () => {
+    expect(anagrams('One one', 'One one c')).toBeFalsy();
+    expect(easyAnagram('One one', 'One one c')).toBeFalsy();
+  });
+
+  test('"A tree, a life, a bench" is not an anagram of "A tree, a fence, a yard"', () => {
+    expect(
+      anagrams('A tree, a life, a bench', 'A tree, a fence, a yard'),
+    ).toBeFalsy();
+    expect(
+      easyAnagram('A tree, a life, a bench', 'A tree, a fence, a yard'),
+    ).toBeFalsy();
+  });
+});