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Swap Two Numbers Without Extra Variable

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Your question is Swap Two Numbers Without Extra Variable. Start with the requirements on the right.

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Problem

ValueMomentum services sometimes transform compact integer buffers in place to reduce temporary allocations. Implement a function that swaps the integers at two positions without using an extra variable, tuple unpacking, or creating another array.

Use the XOR-swap technique. The input list must be modified directly, and the function must return the same list object.

Formal Specification

Given an integer list values and valid indices i and j, swap values[i] and values[j] in place. Return values. All list elements are integers, and i and j may refer to the same position.

Constraints

  • 1 <= len(values) <= 10^5
  • -10^18 <= values[k] <= 10^18
  • 0 <= i, j < len(values)
  • The function must use O(1) auxiliary space
  • Do not use a temporary variable, tuple unpacking, slicing, or another list

Function Signature

def swap_without_temp(values, i, j):
Your solutionPython 3
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