From 4dff3524b36168ee72c7a944a06b09e6efdb552f Mon Sep 17 00:00:00 2001
From: Gonzalo Diaz <devel@gon.cl>
Date: Mon, 21 Jul 2025 15:41:10 -0400
Subject: [PATCH] =?UTF-8?q?[Hacker=20Rank]=20Interview=20Preparation=20Kit?=
 =?UTF-8?q?:=20Miscellaneous:=20Flipping=20bits.=20New=20way=20to=20solve?=
 =?UTF-8?q?=20=E2=9C=85.?=
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---
 .../flipping-bits-alt-solution-notes.md       | 14 +++++++++
 .../miscellaneous/flipping-bits-alt.test.ts   | 31 +++++++++++++++++++
 .../miscellaneous/flipping-bits-alt.ts        | 12 +++++++
 3 files changed, 57 insertions(+)
 create mode 100644 docs/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt-solution-notes.md
 create mode 100644 src/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt.test.ts
 create mode 100644 src/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt.ts

diff --git a/docs/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt-solution-notes.md b/docs/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt-solution-notes.md
new file mode 100644
index 00000000..804ef5a4
--- /dev/null
+++ b/docs/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt-solution-notes.md
@@ -0,0 +1,14 @@
+# [Miscellaneous: Flipping bits](https://www.hackerrank.com/challenges/flipping-bits)
+
+- Difficulty:  `#easy`
+- Category: `#ProblemSolvingBasic` `#BitManipulation`
+
+## Using bitwise operations
+
+The bitwise NOT operator (~) flips all bits of the number.
+
+The & 0xFFFFFFFF ensures that we only keep the last 32 bits,
+effectively simulating a 32-bit unsigned integer.
+
+This is a more efficient and concise way to achieve the same result
+as the original code, without needing to convert to binary strings.
diff --git a/src/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt.test.ts b/src/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt.test.ts
new file mode 100644
index 00000000..1c129f15
--- /dev/null
+++ b/src/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt.test.ts
@@ -0,0 +1,31 @@
+import { describe, expect, it } from '@jest/globals';
+import { logger as console } from '../../../logger';
+
+import { flippingBitsAlt } from './flipping-bits-alt';
+
+import TEST_CASES from './flipping-bits.testcases.json';
+
+describe('flipping bits', () => {
+  it('flipping bits test cases', () => {
+    expect.assertions(10);
+
+    let totalTestsCount = 0;
+
+    TEST_CASES.forEach((testSet) => {
+      testSet.tests.forEach((test) => {
+        const answer = flippingBitsAlt(test.input);
+
+        console.debug(
+          `flippingBitsAlt(${test.input}) solution found: ${answer}`
+        );
+
+        expect(answer).toStrictEqual(test.expected);
+
+        totalTestsCount += 1;
+      });
+    });
+
+    expect(TEST_CASES).toHaveLength(3);
+    expect(totalTestsCount).toBe(8);
+  });
+});
diff --git a/src/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt.ts b/src/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt.ts
new file mode 100644
index 00000000..dd55c849
--- /dev/null
+++ b/src/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt.ts
@@ -0,0 +1,12 @@
+/**
+ * @link Problem definition [[docs/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits.md]]
+ * @see Solution notes [[docs/hackerrank/interview_preparation_kit/miscellaneous/flipping-bits-alt-solution-notes.md]]
+ */
+
+function flippingBitsAlt(n: number): number {
+  // eslint-disable-next-line no-bitwise
+  return ~n >>> 0;
+}
+
+export default { flippingBitsAlt };
+export { flippingBitsAlt };