we all know the simple swap function: void swap(int &num1, int &num2) { int temp; temp=num1; num1=num2; num2=temp; } fine and dandy. Just one problem, it declares an extra variable (temp). How do you swap the numbers without that extra variable and, this is a big one, WITHOUT OVERFLOW? I remember seeing something about this one time. If you weren''t worried about overflow, you could do it like this: num1+=num2; num2=num1-num2; num1-=num2; I seem to remember something about ORs and XORs...

num1 ^= num2;
num2 ^= num1;
num1 ^= num2;

Make sure you are not swapping the same variables or you will screw the XORings

If you want to write a function for it, declare it as inline.

You could use some inline assembly:

mov EAX, First
xchg EAX, Second
mov First, EAX