Variations
The underlying principle of the XOR swap algorithm can be applied to any operation meeting criteria L1 through L4 above. Replacing XOR by addition and subtraction gives a slightly different, but largely equivalent, formulation:
void addSwap (unsigned int *x, unsigned int *y) { if (x != y) { *x = *x + *y; *y = *x - *y; *x = *x - *y; } }Unlike the XOR swap, this variation requires that the underlying processor or programming language uses a method such as modular arithmetic or bignums to guarantee that the computation of X + Y cannot cause an error due to integer overflow. Therefore, it is seen even more rarely in practice than the XOR swap.
Read more about this topic: XOR Swap Algorithm
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