Discussion on: Algorithms Problem Solving: Reduce to zero

[FriesischScott]

While this is a perfectly valid solution to the problem, this is a problem where recursion really shines and removes the need for a loop.

def reduce_number(num, counter=0):
    if num == 0:
        return counter

    if num % 2 == 0:
        return reduce_number(num / 2, counter + 1)
    else:
        return reduce_number(num - 1, counter + 1)

[Joe Zack]

The recursive solution is prettier, but it's not doing any less work and it ties up more memory unless your language supports tail recursion (python doesn't)

I try to avoid recursive solutions for problems like these unless the solution specifically needs back tracking.

[FriesischScott]

Never heard of tail recursion before. I'll look it up, thanks.