Asked about The high-frequency patterns

How do you recognise a sliding window problem?

An answer that works

It asks about a contiguous subarray or substring with some property, usually the longest or shortest satisfying a condition. The shape is always expand with the loop, contract when the property breaks.

Reading an answer is not being able to give one. The section that teaches this is The high-frequency patterns, 16 hours of Data structures & algorithms.

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