Algorithm interview from Google

Question

I am a long time lurker, and just had an interview with Google where they asked me this question:

Various artists want to perform at the Royal Albert Hall and you are re

Answer 1

Store the scheduled concerts in a binary search tree and find a feasible solution by doing a binary search.

Something like this:

FindDateAfter(tree, x):
  n = tree.root
  if n.date < x 
    n = FindDateAfter(n.right, x)
  else if n.date > x and n.left.date < x
    return n
  return FindDateAfter(n.left, x)

FindGoodDay(tree, x):
  n = FindDateAfter(tree, x)
  while (n.date + 10 < n.right.date)
    n = FindDateAfter(n, n.date + 5)
  return n.date + 5