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traeki

Posts: 8

Joined: Mon May 16, 2005 4:10 pm

Post Mon May 16, 2005 8:35 pm

traeki wrote:Okay...I'm having a problem that really annoys me. The epoch wasn't that long ago. This may or may not actually be relevant for the puzzle, but can anybody tell me how to work around that? Cheers,

-John


Okay -- I figured that out, and I got to the next stage, but I still honestly don't understand how you're supposed to disambiguate amongst the years. ::shrugs:: I guess trial and error isn't too painful...

-John
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UncleTimmy

Posts: 118

Joined: Thu May 05, 2005 3:44 pm

Post Tue May 17, 2005 7:09 am

traeki wrote:... but I still honestly don't understand how you're supposed to disambiguate amongst the years. ::shrugs:: I guess trial and error isn't too painful...
-John


Not needed -- read the clues in the page source. He ain't the third either :wink:
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newsham

Posts: 3

Joined: Sat May 21, 2005 2:37 am

Location: Oahu, HI

Post Sat May 21, 2005 2:40 am

There's a bug in one of the libraries you could use to solve this.
It doesn't affect the date in question, but it does affect some of
the potentially matching dates. Compare with output of "cal"
for sanity. Dates are hard, especially older ones.

I could provide more details but I dont want to be a spoiler.
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UncleTimmy

Posts: 118

Joined: Thu May 05, 2005 3:44 pm

Post Sat May 21, 2005 9:34 am

newsham wrote:There's a bug in one of the libraries you could use to solve this.
It doesn't affect the date in question, but it does affect some of
the potentially matching dates. Compare with output of "cal"
for sanity. Dates are hard, especially older ones.

I could provide more details but I dont want to be a spoiler.


It's not a secret that Python has `calendar` and `datetime` modules. Using Python 2.4.1, and using all the clues, I get the same list of possible years using either. Which module and Python version do you have in mind?

Note that the Python modules document that they use the proleptic Gregorian calendar, which assumes the Gregorian calendar has always been in use. The Unix(tm) `cal` pegged the transition date in 1752, presumably because that's when Great Britain and America finally switched. But in truth many European countries switched more than a century earlier, some in 1582 already (the year Pope Gregory introduced this calendar reform).

At least Python is up front about refusing to pretend that "the world" means America here :wink:.
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newsham

Posts: 3

Joined: Sat May 21, 2005 2:37 am

Location: Oahu, HI

Post Sat May 21, 2005 1:12 pm

So take the results from those modules and compare to the results from
unix "cal". Note that there exist dates earlier than 1582. I don't see
how blaming unix's americentricisms is relevant (keep in mind that
unix was written in new jersey, not hamburg).
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drigz

Posts: 23

Joined: Sat May 21, 2005 9:41 am

Post Sat May 21, 2005 3:40 pm

I have a list of years (with 10 items) but none appear in wikipedia's january 27 list... what might be wrong with my method?
Last edited by drigz on Sun May 22, 2005 12:56 am, edited 1 time in total.
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thesamet

Python Challenge Leader

Posts: 69

Joined: Thu Apr 28, 2005 11:02 pm

Post Sat May 21, 2005 3:41 pm

drigz wrote:I have a list of years (with 10 items) but none appear in wikipedia's january 17 list... what might be wrong with my method?


maybe nothing. look at the source again.
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UncleTimmy

Posts: 118

Joined: Thu May 05, 2005 3:44 pm

Post Sat May 21, 2005 3:41 pm

newsham wrote:So take the results from those modules and compare to the results from
unix "cal". Note that there exist dates earlier than 1582. I don't see
how blaming unix's americentricisms is relevant (keep in mind that
unix was written in new jersey, not hamburg).


Sorry, I don't know what you're talking about -- neither here, nor in your msg where you said there's "a bug". Specifically what bug? For example, Python's modules and "cal" don't agree for the year 1356. If that's what you're talking about, no, that's not a bug (for reasons already explained: the proleptic Gregorian calendar is not the same as Unix's British-American calendar).
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d2718j

Posts: 5

Joined: Sun May 22, 2005 12:39 am

Post Sun May 22, 2005 12:58 am

stuck

I was doing good until I hit #15. I've read the hints, and still don't get it.

I used cal (and a shell script) to come up with a list of the years that satisfy the obvious constraint of the calendar, given the clue that two digits are missing.

The circled date is Jan 26, and I've googled for that on the various dates.

The file name of the image seemed like a big clue, that would narrow it down to one date (the most recent). But I don't see anything standing out for Jan 26 or anything near that. Something about Patty Hearst on Jan 27, but that's obviously not what's intended.

Any other clues?
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UncleTimmy

Posts: 118

Joined: Thu May 05, 2005 3:44 pm

Post Sun May 22, 2005 9:26 am

Re: stuck

d2718j wrote:...I used cal (and a shell script) to come up with a list of the years that satisfy the obvious constraint of the calendar, given the clue that two digits are missing.


That's not the only constraint.

The circled date is Jan 26, and I've googled for that on the various dates.


The intended date is specified uniquely, but sounds like you haven't yet found (or recognized) all the constraints.

The file name of the image seemed like a big clue, that would narrow it down to one date (the most recent)


:?: The image name is screen15.jpg, and this is level 15. Not sure what you see in the name deeper than just that. Have you read the rest of the page source?

... Any other clues?


Yes, there are :wink:
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drigz

Posts: 23

Joined: Sat May 21, 2005 9:41 am

Post Sun May 22, 2005 10:30 am

I'm really having trouble with this problem. The following rot13 encrypted POTENTIAL SPOILER details my progress (numbers encrypted rot5):

V unir perngrq n cebtenz jvgu gur qngrgvzr zbqhyr gung svaqf nyy qngr(6551 + 65*v, 6, 71).vfbjrrxqnl() == 6, naq unir tbggra n yvfg bs 65 lrnef (vapyhqvat 6591 naq 6391). Sebz gur fbhepr, V unir pbzr gb gur pbapyhfvba gung vg vf gur crahygvzngr qngr va guvf yvfg, naq gung gur npghny rirag bppheerq ba gur 72gu. Ubjrire, ybbxvat ba Jvxvcrqvn'f yvfg bs riragf bppheevat ba Wnahnel 7{1,2}guf, V unir abg orra noyr gb svaq na rirag juvpu bppheerq ba nal lrne va zl yvfg. Jung unir V qbar jebat?

Thanks for any help.
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d2718j

Posts: 5

Joined: Sun May 22, 2005 12:39 am

Post Sun May 22, 2005 10:48 am

Re: stuck

The circled date is Jan 26, and I've googled for that on the various dates.

The intended date is specified uniquely, but sounds like you haven't yet found (or recognized) all the constraints.


Okay. Any useful clues?

The file name of the image seemed like a big clue, that would narrow it down to one date (the most recent)

:?: The image name is screen15.jpg, and this is level 15. Not sure what you see in the name deeper than just that. Have you read the rest of the page source?


It's a screen shot of someone's calendar, i.e., a picture of a computer-image of a calendar. Hence the name "screen". The image name as been significant before (evil1). The number doesn't seem significant here, except that it's problem 15. So I'm guessing the name "screen" is calling attention to the fact that it's a picture of a computer screen.

... Any other clues?
Yes, there are :wink:


Any helpful clues? From the other comments this seems like a pretty lame one. Is there a way to skip it and go to the next?
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UncleTimmy

Posts: 118

Joined: Thu May 05, 2005 3:44 pm

Post Sun May 22, 2005 1:26 pm

Re: stuck

d2718j wrote:... Okay. Any useful clues?


It's hard to give you more without giving the answer outright. For example, you were asked whether you read the rest of the page source, but no answer. Or when someone who has solved the level suggests that staring at the image name isn't helpful here, take the hint instead of trying to salvage the guess that "it should be" helpful :wink:.

... Is there a way to skip it and go to the next?


Not that I know of. Everyone has problems with some levels, but different people struggle with different levels. This one seems particularly hard for you, but was particularly easy for others. So it goes. Everything you need to solve it is there.
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UncleTimmy

Posts: 118

Joined: Thu May 05, 2005 3:44 pm

Post Sun May 22, 2005 1:49 pm

drigz wrote:I'm really having trouble with this problem. The following rot13 encrypted POTENTIAL SPOILER details my progress (numbers encrypted rot5):...


You're doing very well, although you're looking at too many years because you missed a clue (what's an obvious difference between 2005 and 2004? there's a clue here that tells you the same about the year you're looking for).

The way you're looking for the significance of the date can work, but is much harder than necessary. Try a search engine instead, like a normal person would :wink:.
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d2718j

Posts: 5

Joined: Sun May 22, 2005 12:39 am

Post Sun May 22, 2005 1:52 pm

Re: stuck

UncleTimmy wrote:
d2718j wrote:... Okay. Any useful clues?


For example, you were asked whether you read the rest of the page source, but no answer.



Well of course I read the source page. So many of the puzzles prior to this involved reading the page source that it's usually the first thing I do.


Or when someone who has solved the level suggests that staring at the image name isn't helpful here, take the hint instead of trying to salvage the guess that "it should be" helpful


I wasn't trying to explain why it "should be" helpful, just explaining why it looked like it might be. I'll take your word for it that the fact that it is an image of a computer screen, with the name "screen", are just red herrings. The year might be one in which the format in which the calendar is presented would be impossible.

... Is there a way to skip it and go to the next?

Not that I know of. Everyone has problems with some levels, but different people struggle with different levels. This one seems particularly hard for you, but was particularly easy for others. So it goes. Everything you need to solve it is there.


Here's a specific question:

One person mentioned a "bug" in the date calculation. Obviously calendar dates are ambiguous when you go back far enough. Is this an issue, such that the calendar assumptions made by the "cal" command might not be compatible?

Also, another person mentioned that Wikipedia had the date off by one. Is that right, i.e., this puzzle hinges on a date that may or may not be accurate depending on the source you look at?
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