The Unique Batch

A factory produces components with serial numbers. To ensure quality, the testing machine checks batches of exactly W consecutive components. A batch is only 'valid' if every component in that batch has a unique serial number. Count how many valid batches exist in the production stream. Input Format: - The first line contains two integers: W (the batch size) and N (the total number of components). - The second line contains N space-separated integers representing the serial numbers. Output Format: - Print the number of valid batches. Example: Input: 3 6 1 2 3 2 1 4 Output: 3 Explanation: The valid batches are [1, 2, 3], [3, 2, 1], and [2, 1, 4]. [2, 3, 2] is invalid due to duplicate 2s.