Help with map python 2

flebber flebber.crue at gmail.com
Sun Jan 4 12:34:21 CET 2015


In repsonse to this question: Write a program that prints the first 100 members of the sequence 2, -3, 4, -5, 6, -7, 8.

This is my solution it works but ugly.

series = range(2,100)
# answer = [(x,(y* -1)) for x, y in series[::2]]
# print(answer)
answer = []
for item in series:
    if item % 2 != 0:
        answer.append(item * -1)
    else:
        answer.append(item)

print(answer)

I know I should be better off doing this with map but cannot get it to work. I understand also that map returns a generator so this solution should only working in python2(correct me please if I am wrong).

In [6]: map?
Type:       builtin_function_or_method
String Form:<built-in function map>
Namespace:  Python builtin
Docstring:
map(function, sequence[, sequence, ...]) -> list

Just getting something wrong
list(map((lambda x: x * -1 if (x%2 != 0)), series))



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