#!/usr/bin/env python2


def bin_search(a, val, lo, hi):
  print "%d %d"%(lo, hi)
  if hi < lo:
    return -1
  mid = (lo+hi)/2
  if a[mid] > val:
    return bin_search(a, val, lo, mid-1)
  elif a[mid] < val:
    return bin_search(a, val, mid+1, hi)
  else:
    return mid


a = [1, 2, 3, 4, 5, 6, 7, 8]
#    0  1  2  3  4  5  6  7

if bin_search(a, 3, 0, len(a)-1):
  print "Yay!"
else:
  print ":-("