This pull request adds a new evenOrOdd function in the Bit Manipulation folder to check if a number is even or odd using bitwise operations. It includes error handling for wrong inputs and test cases to make sure it works properly. This addition improves our JavaScript algorithms collection!

Bit-Manipulation/EvenorOdd.js

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+/**
+ *
+ *  This script will check whether a number is even or odd
+ *    using bit manipulation.
+ *  Idea:
+ *  A number can be determined as even or odd by the lsb(least significant bit) or the
+ *  right most bit in binary representation
+ *  if we simply perform an and operation with 1 and the number we can determine:
+ *  eg:
+ *  number & 1 == 1, the number is odd
+ *  number & 1 == 0, the number is even
+ *
+ * More about it :
+ * https://www.geeksforgeeks.org/check-if-a-number-is-odd-or-even-using-bitwise-operators/
+ *
+ */
+
+export const evenOrOdd = (number) => {
+  if (typeof number !== 'number' || !Number.isInteger(number)) {
+    throw new Error('Input must be an integer.')
+  }
+  return number & 1 ? 'odd' : 'even'
+}

Bit-Manipulation/test/EvenorOdd.test.js

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+import { evenOrOdd } from '../EvenorOdd'
+
+test('check evenOrOdd of 25 is odd', () => {
+  const res = evenOrOdd(25)
+  expect(res).toBe('odd')
+})
+
+test('check evenOrOdd of 36 is even', () => {
+  const res = evenOrOdd(36)
+  expect(res).toBe('even')
+})
+
+test('check evenOrOdd of 0 is even', () => {
+  const res = evenOrOdd(0)
+  expect(res).toBe('even')
+})
+
+test('check evenOrOdd of -13 is odd', () => {
+  const res = evenOrOdd(-13)
+  expect(res).toBe('odd')
+})
+
+test('check evenOrOdd of 4294967295 is odd', () => {
+  const res = evenOrOdd(4294967295)
+  expect(res).toBe('odd')
+})
+
+test('check evenOrOdd of -36 is even', () => {
+  const res = evenOrOdd(-36)
+  expect(res).toBe('even')
+})
+
+test('check evenOrOdd of 21.1 throws error', () => {
+  expect(() => evenOrOdd(21.1)).toThrow()
+})
+
+test('check evenOrOdd of {} throws error', () => {
+  expect(() => evenOrOdd({})).toThrow()
+})