'''
   varargs.py - Demos variable number of arguments in Python.

   Jed Yang, 2017-09-17
'''

def add_array(lst):
   '''Returns the sum of numbers in the list lst.'''
   a = 0
   for b in lst:
      a += b
   return a

print(add_array([]))
print(add_array([1]))
print(add_array([1, 2]))
print(add_array([1, 2, 3, 4, 5]))

def add_vargs(*lst):
   '''Returns the sum of the arguments.'''
   a = 0
   for b in lst:
      a += b
   return a

print(add_vargs())
print(add_vargs(1))
print(add_vargs(1, 2))
print(add_vargs(1, 2, 3, 4, 5))