This question was asked during IBM’s interview in our campus in 2005:
How would you swap two integers in one statement without using a temporary variable in C/C++?
After thinking about it for some time, this is what I got (this is in Java):
class Swap
{
public static void main( String[] args )
{
int a, b;
a = 46;
b = 47;
System.out.println( "a = " + a + ", b = " + b );
a = b | ( 0 & (b = a));
System.out.println( "a = " + a + ", b = " + b );
}
}
However, the interviewer gave a hint that it requires the use of XOR operator. If any one of you can think of a solution using XOR, please post your solution here.