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Algorithms & data structures easy

Reorder a List by Odd Even Indices in Python

Splits a list into two sublists based on 1-based index parity, then concatenates odd-indexed elements before even-indexed ones.

list indices reorder
Python 
def reorder_by_odd_even(items):
    """Reorders a list so that elements at odd indices come first,
    followed by elements at even indices (1-based).
    
    Example: [0,1,2,3,4,5,6] -> [1,3,5,0,2,4,6]
    """
    odds = [items[i] for i in range(1, len(items), 2)]
    evens = [items[i] for i in range(0, len(items), …
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