feat: add maxConsecutiveOnes implementation (TheAlgorithms#1285)

HereBeAndre · web-flow · commit 5ce828b3fe4e · 2023-02-13T17:11:28.000+05:30
diff --git a/Dynamic-Programming/Sliding-Window/MaxConsecutiveOnes.js b/Dynamic-Programming/Sliding-Window/MaxConsecutiveOnes.js
@@ -0,0 +1,30 @@
+/**
+ * @function maxConsecutiveOnes
+ * @description Given a binary array nums, return the maximum number of consecutive 1's in the array.
+ * @param {number[]} nums
+ * @return {number}
+ * @see [Leetcode link](https://leetcode.com/problems/max-consecutive-ones/)
+ */
+export const maxConsecutiveOnes = (nums) => {
+  if (!nums.length) return 0
+
+  let result = 0
+  let k = 0
+
+  for (
+    let slowPointer = 0, fastPointer = 0;
+    fastPointer < nums.length;
+    fastPointer++
+  ) {
+    if (nums[fastPointer] === 0) k--
+
+    while (k < 0) {
+      if (nums[slowPointer] === 0) {
+        k++
+      }
+      slowPointer++
+    }
+    result = Math.max(result, fastPointer - slowPointer + 1)
+  }
+  return result
+}
diff --git a/Dynamic-Programming/Sliding-Window/test/MaxConsecutiveOnes.test.js b/Dynamic-Programming/Sliding-Window/test/MaxConsecutiveOnes.test.js
@@ -0,0 +1,19 @@
+import { maxConsecutiveOnes } from '../MaxConsecutiveOnes.js'
+
+describe('maxConsecutiveOnes', () => {
+  it('expects to return 0 when argument is empty array', () => {
+    expect(maxConsecutiveOnes([])).toBe(0)
+  })
+
+  it('expects to return 3', () => {
+    expect(maxConsecutiveOnes([1, 1, 0, 1, 1, 1])).toBe(3)
+  })
+
+  it('expects to return 2', () => {
+    expect(maxConsecutiveOnes([1, 0, 1, 1, 0, 1])).toBe(2)
+  })
+
+  it('expects to return 5', () => {
+    expect(maxConsecutiveOnes([0, 1, 1, 1, 1, 1, 0, 0, 1, 0])).toBe(5)
+  })
+})
