numbers = [-3, 101, 97, -13, 41]
positive_numbers = list()
negative_numbers = list()
'''
while I didn't reach the end of the collection:
1. check if element's value is > 0
add to positive
2. otherwise check if element's value is < 0
add to negative
increment the step to the next element
'''
start = 0
step = start
stop = len(numbers)
# while I didn't reach the end of the collection:
while step < stop:
element = numbers[step]
# 1. check if element's value is > 0
# add to positive
if element > 0:
positive_numbers.append(element)
# 2.otherwise check if element 's value is < 0
# add to negative
elif element < 0:
negative_numbers.append(element)
# increment the step to the next element
step = step + 1
