@LeakyNun To be fair, alphabet challenges can be interesting to golf depending on the language... it's just when there's too many of them at once and there's also the fact that they don't takeasmuchtimetocomeupwithbutgetlotsofvotesfromHNQmaybeI'malittlejealous
Introduction
Alphabet challenges are in our DNA, so let's show it.
Challenge
Print the following the text exactly:
AaBbCc cCbBaA
BbCcDd dDcCbB
EeFfGg gGfFeE
HhIiJj jJiIhH
KkLlMm mMlLkK
NnOoPp pPoOnN
QqRrSs sSrRqQ
TtUuVv vVuUtT
WwXx ...
In the game of sudoku, many players like to "pencil in" possible numbers that can go in each square:
The above row can be represented as an array:
[[1,2,9], [6], [5], [7], [1,2,9], [1,2,9], [3], [1,2,4], [8]]
Now, notice that there is only 1 place where a 4 can go. This effectively lets us...
$ time foo
real 0m0.003s
user 0m0.000s
sys 0m0.004s
$
What do 'real', 'user' and 'sys' mean in the output of time?
Which one is meaningful when benchmarking my app?
@LeakyNun er, I don't think your program works with "[[9:0:2:3:7]:[0:7:6:5]:[6:9:4:7]:[9:1:2:3:0:5]:[2:8:5:7:4:6]:[6:5:7:1]:[5:9:4]:[5:9:3:8:1]:[5:0:6:4]:[0:7:2:1:3:4:8]]"
I didn't think we had a requirement to pre-solve challenges before they were posted. I know that I very rarely solve challenges I post. I swear I had read Helka post once that (he) almost never solves challenges before posting, but I can't seem to find it.
Hmm. I missed that when I was first reading the chat log here. Yeah, that's more of a grey area. Kinda like requiring a certain complexity without a proof.
C:\Users\XXX>python -m timeit "b=10000;c=b+b"
10000000 loops, best of 3: 0.0581 usec per loop
C:\Users\XXX>python -m timeit "b=10000;c=b*2"
10000000 loops, best of 3: 0.0612 usec per loop
C:\Users\XXX>python -m timeit "b=10000;c=b<<1"
10000000 loops, best of 3: 0.0683 usec per loop
@EᴀsᴛᴇʀʟʏIʀᴋ But it's weird that << is slowest because in theory it should be the fastest. At the circuit level it's just routing the wires one bit over.
@HelkaHomba it may be related to the arbitrary precision checking
(but then, so are others)
C:\Users\XXX>python -m timeit "b=10000;c=b*b"
10000000 loops, best of 3: 0.0621 usec per loop
C:\Users\XXX>python -m timeit "b=10000;c=b**2"
1000000 loops, best of 3: 0.259 usec per loop
Lesson learnt: don't think that using built-ins can optimize.
@LeakyNun if b: would be ever so slightly faster. If clarity is important/useful, go with if b==1:. It's for this reason that I sometimes write if b == 0: instead of if not b: when the latter is confusing because of what b is. Hmm, that would be clearer with an example...
@LeakyNun Though frankly, if you're looking for speed boosts, learning C++ instead of trying to optimizing Python is probably a better time investment.
@LeakyNun It seems to me like you're either checking a number for primality, in which case the limit is how big the factors can be (sqrt(p)), or you're getting a list of primes, in which case, the limit is how big the primes can be.
That awkward moment when you prefer writing in vim but your co-worker uses a crappy IDE that inserts tabs and you use spaces in vim which screws with source control revision history...
@LeakyNun The first one is essentially Sieve of Eratosthenes, isn't it? At least, one where the upper bound expands as needed to get the desired number of primes.
@DJMcMayhem That editor is a keeper. Why would an editor default to insert spaces when you press the tab key? I mean, you certainly wouldn't expect the spacebar to insert tabs...
Woah. TIL that python2 allows spaces and tabs together
Python 2.7.11 (v2.7.11:6d1b6a68f775, Dec 5 2015, 20:40:30) [MSC v.1500 64 bit (
AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> if 1:
... print("t")
... print("s")
...
t
s
>>>
@DJMcMayhem That kind of backfired for me. Once I enabled that, I wasted even more time on trying to bypass it than I would have wasted on the blocked website.
Introduction
Alphabet challenges are in our DNA, so let's show it.
Challenge
Print the following the text exactly:
AaBbCc cCbBaA
BbCcDd dDcCbB
EeFfGg gGfFeE
HhIiJj jJiIhH
KkLlMm mMlLkK
NnOoPp pPoOnN
QqRrSs sSrRqQ
TtUuVv vVuUtT
WwXx ...
In the game of sudoku, many players like to "pencil in" possible numbers that can go in each square:
The above row can be represented as an array:
[[1,2,9], [6], [5], [7], [1,2,9], [1,2,9], [3], [1,2,4], [8]]
Now, notice that there is only 1 place where a 4 can go. This effectively lets us...
$ time foo
real 0m0.003s
user 0m0.000s
sys 0m0.004s
$
What do 'real', 'user' and 'sys' mean in the output of time?
Which one is meaningful when benchmarking my app?
