how swap two strings without using 3rd variable? could it be done using constructors?

[GCDEF]

The only situation where it is possible to swap standard null terminated strings without using a 3rd variable is when they are exactly the same size (or the memory allocated for the smaller string is at least that of the larger string). See example below. This also assumes that the max ASCII value of any individual char in the string is 127 otherwise *p1 += *p2 will overflow the bounds of a char.

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