Selection Test 2013 Facebook Hackaton Given two positive integers n and k, generate all binary integer between 0 and 2 ** n-1, inclusive. These binaries will be drawn in descending order according to the number of existing 1s. If there is a tie choose the lowest numerical value. Return the k-th element from the selected list. Eg n = 3 and k = 5 …

facebook_hackaton.py

def hack1(n, k):
  def f(s):
    return s.count('1')
  binaries = []
  for x in range(2**n):
    binaries.append(bin(x))
  binaries.sort(key=f, reverse = True)
  return binaries[k - 1]

def hack(n, k):
  return sorted([bin(x) for x in range(2**n)],
                key=lambda s: s.count('1'),
                reverse = True)[k-1]
  

Seems that the links provided above changed to:

https://gist.github.com/douglasdrumond/5655684

and

https://gist.github.com/douglasdrumond/5655686

Thanks Fernando for those gists!