From 0de1aa1cd7ebbce8324b5668aa04ff50a6e8426e Mon Sep 17 00:00:00 2001
From: nickzerjeski <nick@zerjeski.de>
Date: Mon, 13 Apr 2026 11:02:33 +0200
Subject: [PATCH 1/3] feat: add meta binary search algorithm

Fixes: #1835
---
 Search/MetaBinarySearch.js           | 28 ++++++++++++++++++++++++++++
 Search/test/MetaBinarySearch.test.js | 21 +++++++++++++++++++++
 2 files changed, 49 insertions(+)
 create mode 100644 Search/MetaBinarySearch.js
 create mode 100644 Search/test/MetaBinarySearch.test.js

diff --git a/Search/MetaBinarySearch.js b/Search/MetaBinarySearch.js
new file mode 100644
index 0000000000..b0c19e9a72
--- /dev/null
+++ b/Search/MetaBinarySearch.js
@@ -0,0 +1,28 @@
+/**
+ * Meta Binary Search
+ * https://www.geeksforgeeks.org/meta-binary-search-one-sided-binary-search/
+ *
+ * Builds the index bit by bit from the most-significant bit to the least-significant bit.
+ * Works on sorted arrays and returns the index of target, or -1 if not found.
+ */
+
+function metaBinarySearch(sortedArray, target) {
+  if (!Array.isArray(sortedArray) || sortedArray.length === 0) {
+    return -1
+  }
+
+  const n = sortedArray.length
+  const maxBit = Math.floor(Math.log2(n - 1 < 0 ? 0 : n - 1))
+
+  let position = 0
+  for (let bit = maxBit; bit >= 0; bit--) {
+    const candidate = position | (1 << bit)
+    if (candidate < n && sortedArray[candidate] <= target) {
+      position = candidate
+    }
+  }
+
+  return sortedArray[position] === target ? position : -1
+}
+
+export { metaBinarySearch }
diff --git a/Search/test/MetaBinarySearch.test.js b/Search/test/MetaBinarySearch.test.js
new file mode 100644
index 0000000000..9b58cfd5b1
--- /dev/null
+++ b/Search/test/MetaBinarySearch.test.js
@@ -0,0 +1,21 @@
+import { metaBinarySearch } from '../MetaBinarySearch'
+
+describe('Meta Binary Search', () => {
+  test('returns index for found numeric element', () => {
+    expect(metaBinarySearch([2, 5, 8, 12, 16, 23, 38], 23)).toBe(5)
+  })
+
+  test('returns -1 when numeric element is missing', () => {
+    expect(metaBinarySearch([2, 5, 8, 12, 16, 23, 38], 9)).toBe(-1)
+  })
+
+  test('works with sorted strings', () => {
+    expect(metaBinarySearch(['alpha', 'beta', 'delta', 'omega'], 'delta')).toBe(
+      2
+    )
+  })
+
+  test('returns -1 on empty input', () => {
+    expect(metaBinarySearch([], 1)).toBe(-1)
+  })
+})

From 3a48a803b0a3362bc3315c476527fc1bee9912a8 Mon Sep 17 00:00:00 2001
From: nickzerjeski <nickzerjeski@users.noreply.github.com>
Date: Mon, 13 Apr 2026 09:09:12 +0000
Subject: [PATCH 2/3] Updated Documentation in README.md

---
 DIRECTORY.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/DIRECTORY.md b/DIRECTORY.md
index b7b8aca45d..b3511a1372 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -314,6 +314,7 @@
   * [InterpolationSearch](Search/InterpolationSearch.js)
   * [JumpSearch](Search/JumpSearch.js)
   * [LinearSearch](Search/LinearSearch.js)
+  * [MetaBinarySearch](Search/MetaBinarySearch.js)
   * [Minesweeper](Search/Minesweeper.js)
   * [QuickSelectSearch](Search/QuickSelectSearch.js)
   * [RabinKarp](Search/RabinKarp.js)
@@ -322,8 +323,8 @@
   * [TernarySearch](Search/TernarySearch.js)
   * [UnionFind](Search/UnionFind.js)
 * **Sliding-Windows**
-  * [MaxSumSubarrayFixed](Sliding-Windows/MaxSumSubarrayFixed.js)
   * [LongestSubarrayWithSumAtMost](Sliding-Windows/LongestSubarrayWithSumAtMost.js)
+  * [MaxSumSubarrayFixed](Sliding-Windows/MaxSumSubarrayFixed.js)
 * **Sorts**
   * [AlphaNumericalSort](Sorts/AlphaNumericalSort.js)
   * [BeadSort](Sorts/BeadSort.js)

From b2269fc286e7f60fe31275a15efd1a5ffcbc2d1f Mon Sep 17 00:00:00 2001
From: nickzerjeski <nick@zerjeski.de>
Date: Mon, 13 Apr 2026 12:18:00 +0200
Subject: [PATCH 3/3] Address review edge cases in meta binary search

---
 Search/MetaBinarySearch.js           | 4 ++--
 Search/test/MetaBinarySearch.test.js | 4 ++++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/Search/MetaBinarySearch.js b/Search/MetaBinarySearch.js
index b0c19e9a72..c2ef924516 100644
--- a/Search/MetaBinarySearch.js
+++ b/Search/MetaBinarySearch.js
@@ -12,11 +12,11 @@ function metaBinarySearch(sortedArray, target) {
   }
 
   const n = sortedArray.length
-  const maxBit = Math.floor(Math.log2(n - 1 < 0 ? 0 : n - 1))
+  const maxBit = Math.floor(Math.log2(Math.max(1, n - 1)))
 
   let position = 0
   for (let bit = maxBit; bit >= 0; bit--) {
-    const candidate = position | (1 << bit)
+    const candidate = position + 2 ** bit
     if (candidate < n && sortedArray[candidate] <= target) {
       position = candidate
     }
diff --git a/Search/test/MetaBinarySearch.test.js b/Search/test/MetaBinarySearch.test.js
index 9b58cfd5b1..1609c8ada3 100644
--- a/Search/test/MetaBinarySearch.test.js
+++ b/Search/test/MetaBinarySearch.test.js
@@ -18,4 +18,8 @@ describe('Meta Binary Search', () => {
   test('returns -1 on empty input', () => {
     expect(metaBinarySearch([], 1)).toBe(-1)
   })
+
+  test('returns index for a matching element in a single-element array', () => {
+    expect(metaBinarySearch([7], 7)).toBe(0)
+  })
 })