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Reverse Array In Place
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Reverse Array In Place

EasyPython

Problem

At Spotify, you need to reverse a list of values without allocating another array. Given an array arr, modify it in place so its elements appear in reverse order.

Formal Specification

  • Input: A list of integers arr
  • Output: The same list after being reversed in place
  • Requirement: Do not create a second array for the result

Constraints

  • 0 <= len(arr) <= 10^5
  • -10^9 <= arr[i] <= 10^9
  • The array must be reversed in place
  • Do not allocate a second array for the final result

Function Signature

def reverse_array(arr):
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