Wednesday, June 20, 2012

In place swapping of n digits? Okay done!

    Yesterday in order to solve a coding question I had to swap 4 digits in place! Now I knew the formula to swap 2 digits in place, so I thought, the math cannot be that hard for n number of digits can it?
    Turns out I was right! I tried creating some formulas and then, ahha! I found it! Really simple one! Here it is:
   Say you have variables a,b,c,d and you want to assign values in this fashion:
   a->b b->c c->d d->a. This is how you'll do it:
   a = a+b+c+d
   b = a-b-c-d
   c = a-b-c-d
   d = a-b-c-d
   a = a-b-c-d
   This can simply be extended for n number of digits. Easy naa!