https://www.hackerrank.com/challenges/contacts/submissions/code/37852972

contact_trie.py

actions = int(raw_input())
def node():
  return [0, {}]
contacts = node()
for a in xrange(actions):
  action, word = map(str, raw_input().split())
  cont = contacts
  if action == 'add':
    cont[0] += 1
    for c in word:
      if not cont[1].get(c):
        cont[1][c] = node()
      cont = cont[1].get(c)
      cont[0] += 1
  if action == 'find':
    for c in word:
      cont = cont[1].get(c)
      if not cont:
        break
    print cont[0] if cont else 0