Swapping variables?

^{(doesn't include thinking hours)}

This repository walks though on my implementation of swapping two variables without using a temporary variable or arithmetic operations or XOR.

Algorithm

1. Initialize two variables, a and b, with the values to be swapped.
2. Shift a to the left by the number of bits in b.
3. Perform a bitwise OR between a and b, storing the result in b.
4. Perform a bitwise AND between b and a sequence of 1s matching the number of bits in b, storing the result in a.
5. Shift b to the right by the number of bits in b.
6. Done!

Code

Look at main.c

Complexity

• Time complexity: O(1)
• Space complexity: O(1)

Limitations

This code doesn't work for negative numbers as of now.

No limitations! Apart from the standard space issue same as with arithmetic operations.

Author

• Krish