Doing this on my machine, the despicable snake language comes out ahead

Even a snake can do what other beasts can't. No need to worry. Perl doesn't have a stepping range operator, it doesn't even have a descending one. So the indices must be built every line through. OTOH, knowing that the input lines always contain 10 items, it is trivial to beat the snake: 

qwurx [shmem] ~> time perl -lne 'BEGIN{$,=" "}print+(split)[9,7,5,3,1]
+' in.txt >/dev/null

real    0m1.589s
user    0m1.588s
sys    0m0.004s
qwurx [shmem] ~> time python list.py in.txt >/dev/null

real    0m2.204s
user    0m2.188s
sys    0m0.016s

[download]

And your snake code does - according to the spec Given a line of numbers from a file, print every 2nd number starting from the back - get it right only for an even number of integers:

qwurx [shmem] ~> python
Python 2.7.9 (default, Jun 29 2016, 13:08:31) 
[GCC 4.9.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> line = "1 2 3 4"
>>> line.split()[::-2]
['4', '2']
>>> line = "1 2 3 4 5"
>>> line.split()[::-2]
['5', '3', '1']
>>> ^D

[download]

So, what does every 2nd number starting from the back mean? If we start from the back and take every 2nd, the output for the even example should be ['3','1'], and for the odd example ['4','2']. If we count every 2nd from the beginning, the output ought to be ['4','2'] for both cases.

Because you presented

Example:

1 22 3 -4 ==> -4 22

almost all code examples in this thread assumed that every 2nd meant counting from the beginning, but outputting in reverse order. Tell the snake to do that, and compare again.

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re^3: printing every 2nd entry in a list backwards by shmem
in thread printing every 2nd entry in a list backwards by Anonymous Monk

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