''' Purpose: introduce summing accumulation
'''

# get a list of numbers
reply   = input( 'Enter a list of numbers: ' )
slist   = reply.split()

print()
 
# convert numeric text into numbers one by one
nlist = []  # initialize holder to prepare for adding elements

for s in slist :
    nbr = int( s )
    nlist.append( nbr )

print( "numeric strings:", slist )
print( "integers:", nlist)
print()
# by accumulation get the sum of the numbers
total = 0
# when you're initializing an accumulator, think about the very first run of the for loop
# if you're getting a sum, start at 0 because 0 + n = n
# if you're getting a product, start at 1 because 1 * n = n
#                     string            ""        s + "" = s
#                     list              lst = []       lst.append( element ) -> lst = [ element ]
for nbr in nlist :
    total = total + nbr
    print( "current number:", nbr )
    print( "current total:", total )
    print()

# print summation
print( "sum(", nlist, "):", total )
# there is a built in function called sum( sequence ) that will hand back the sum of a list of numbers
# we do it like this to show accumulation in an easy example with many clear uses, but accumulation is
# very common in computer science

# when you're asked to look at a particular data type, first think about built in functions and methods that
# can help you solve the problem

# we don't name variables sum, max, min, print, append, or you lose the function