Let’s create a music playlist manager for Amazon Music, which allows users to:
- add songs to the playlist
- play a song from the playlist in order
Implement the methods for adding and playing songs.
If the user wants to add another song while the playlist is full, the oldest-added song needs to be removed first.
This problem asks you to build a playlist manager that supports adding songs and playing them in insertion order. The key requirement is FIFO behavior: when the playlist is full, the oldest-added song must be removed before inserting a new one. A queue-like data structure is the natural fit for implementing efficient <code>add</code> and <code>play</code> operations.
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