Fixing null pointer exception on the nextLine()

[edd-ie]

Change Summary

NullPointerException caused by attempting to invoke the method hasMoreTokens() on a StringTokenizer object (st) that is null. This happens in the nextLine() method of your FastReader class.

Ensuring that st is properly initialized before calling hasMoreTokens() in the nextLine() method by modifying the nextLine() method to initialize st if it is null:

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