# Write a function that takes
#    (i) a dictionary whose values are lists of ints, and
#   (ii) a secret int code
# as inputs.
# The function returns first key that maps to a value whose
# sum equals to the secret int code.
# If no sum of the values in the dictionary equals to
# the secret int code, return None

# Example:
#  if the incoming dictionary is {'A':[0,1], 'B':[2,3], 'C':[4,5]}
#     and the secret int code is 5
#     the function returns 'B'
#  if the incoming dictionary is {'A':[0,1], 'B':[2,3], 'C':[4,5]}
#     and the secret int code is 15
#     the function returns None

# You may not use sum(list_of_int) built-in function


def count_sum(dct, secret):











dct = {'A': [0, 1], 'B': [2, 3], 'C': [4, 5]}

print(count_sum(dct, 5))
print(count_sum(dct, 15))