Swap two numbers without a temporary variable

Updated Apr 28, 2026

Short answer

Use three XOR operations: a^=b, b^=a, a^=b.

Deep explanation

This explores bitwise arithmetic and identity properties. Use three XOR operations: a^=b, b^=a, a^=b. These patterns are common in technical coding interviews.

Real-world example

Efficient memory allocation alignment checks.

Common mistakes

  • Not handling the case where n = 0 for power-of-two checks.

Follow-up questions

  • What is the time complexity?

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