MEDIUM Sliding Window

485. Max Consecutive Ones

📖 Problem

Given a binary array nums, return the maximum number of consecutive 1's in the array.

🧠 Visual Learning Aid

1 Model the input into the right structure
2 Choose the core technique and invariant
3 Execute step-by-step with a sample
4 Validate complexity and edge cases

JS/TS Refreshers

  • •Array methods (`push`, `pop`, `shift`, `slice`)
  • •Object/Map/Set usage patterns
  • •Function parameter and return typing
  • •String/array indexing
  • •Set/Map frequency counting
  • •Pointer movement invariants

Logical Thinking Concepts

  • •Define invariants before coding
  • •Check edge cases first (`[]`, single element, duplicates)
  • •Estimate time/space before implementation
  • •Apply Sliding Window reasoning pattern

💡 Approach

  • → Sliding window to track current consecutive ones
  • → Reset count when encountering 0
  • → Track maximum count seen
  • → Time: O(n), Space: O(1)

🧭 Prerequisites

#209 Minimum Size Subarray Sum #424 Longest Repeating Character Replacement

🛠️ Hints & Pitfalls

Hints

  • •Sliding window to track current consecutive ones
  • •Reset count when encountering 0
  • •Track maximum count seen

Common Pitfalls

  • •Time: O(n), Space: O(1)

🧪 Test Cases

Hidden tests on submit: 1

Test Case 1
Not run
Input:
longestOnes([1,1,0,1,1,1]);
Expected:
3
Test Case 2
Not run
Input:
longestOnes([1,0,1,1,0,1]);
Expected:
2
Test Case 3
Not run
Input:
longestOnes([0,0,0,0]);
Expected:
0

📝 Code Editor

📚 Reference Solution

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🔗 Related Problems

#3 Longest Substring Without Repeating Characters #76 Minimum Window Substring #121 Best Time to Buy and Sell Stock #209 Minimum Size Subarray Sum #424 Longest Repeating Character Replacement
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