Hi David,
DN>GW>#define        SWAP(a,b,t)   {t = a;a = b;b = t;}
DN>GW>What is unsafe about it? 
DN>#define SWAP(a,b)  {a ^= b; b ^= a; a ^= b;}
DN>See that! I saved us a temporary storage location. ... :-)
But my way will work on any integral data type (and on structs etc
under C++), will yours?
DN> "The Surgeon General warns ..."   
:-)
George
 * SLMR 2.1a * Wastebasket: Something to throw things near.
--- Maximus/2 3.01
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