Sync LeetCode submission Runtime - 173 ms (25.19%), Memory - 21.7 MB (54.50%)

Author: jimit105

3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i/README.md

@@ -0,0 +1,48 @@
+<p>You are given a <span data-keyword="binary-array">binary array</span> <code>nums</code>.</p>
+
+<p>You can do the following operation on the array <strong>any</strong> number of times (possibly zero):</p>
+
+<ul>
+	<li>Choose <strong>any</strong> 3 <strong>consecutive</strong> elements from the array and <strong>flip</strong> <strong>all</strong> of them.</li>
+</ul>
+
+<p><strong>Flipping</strong> an element means changing its value from 0 to 1, and from 1 to 0.</p>
+
+<p>Return the <strong>minimum</strong> number of operations required to make all elements in <code>nums</code> equal to 1. If it is impossible, return -1.</p>
+
+<p>&nbsp;</p>
+<p><strong class="example">Example 1:</strong></p>
+
+<div class="example-block">
+<p><strong>Input:</strong> <span class="example-io">nums = [0,1,1,1,0,0]</span></p>
+
+<p><strong>Output:</strong> <span class="example-io">3</span></p>
+
+<p><strong>Explanation:</strong><br />
+We can do the following operations:</p>
+
+<ul>
+	<li>Choose the elements at indices 0, 1 and 2. The resulting array is <code>nums = [<u><strong>1</strong></u>,<u><strong>0</strong></u>,<u><strong>0</strong></u>,1,0,0]</code>.</li>
+	<li>Choose the elements at indices 1, 2 and 3. The resulting array is <code>nums = [1,<u><strong>1</strong></u>,<u><strong>1</strong></u>,<strong><u>0</u></strong>,0,0]</code>.</li>
+	<li>Choose the elements at indices 3, 4 and 5. The resulting array is <code>nums = [1,1,1,<strong><u>1</u></strong>,<u><strong>1</strong></u>,<u><strong>1</strong></u>]</code>.</li>
+</ul>
+</div>
+
+<p><strong class="example">Example 2:</strong></p>
+
+<div class="example-block">
+<p><strong>Input:</strong> <span class="example-io">nums = [0,1,1,1]</span></p>
+
+<p><strong>Output:</strong> <span class="example-io">-1</span></p>
+
+<p><strong>Explanation:</strong><br />
+It is impossible to make all elements equal to 1.</p>
+</div>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>3 &lt;= nums.length &lt;= 10<sup>5</sup></code></li>
+	<li><code>0 &lt;= nums[i] &lt;= 1</code></li>
+</ul>

3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i/solution.py

@@ -0,0 +1,25 @@
+# Approach 1: Deque
+
+# Time: O(n)
+# Space: O(n)
+
+from collections import deque
+
+class Solution:
+    def minOperations(self, nums: List[int]) -> int:
+        flip_queue = deque()
+        count = 0
+
+        for i in range(len(nums)):
+            # Remove flips older than 3 indices
+            while flip_queue and i > flip_queue[0] + 2:
+                flip_queue.popleft()
+
+            if (nums[i] + len(flip_queue)) % 2 == 0:
+                if i + 2 >= len(nums):
+                    return -1
+                count += 1
+                flip_queue.append(i)
+
+        return count
+