How to Reverse a List Copy Without Modifying the Original?

Reversing a List Copy Without Intermediate Reversal

In this scenario, the error occurs because the reverse() method modifies the original list in-place and returns None. When we subsequently try to use index() on the modified list, we encounter the NoneType object error.

Solution Using Slicing

One way to avoid the error and obtain a reversed copy of the list is to use slicing. Python slicing follows the format list[::-1], which effectively creates a reversed copy of the list without modifying the original.

Here's how you can apply this technique to the given solution() function:

def solution(formation):
    reversed_list = formation[::-1]  # Create a reversed copy of the list
    return (formation.index(bCamel) > (len(formation) - 1 - reversed_list.index(fCamel)))

This approach provides the desired functionality while avoiding the exception. The reversed_list variable now contains a reversed copy of the input list, which can be used for indexing without affecting the original list.

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