22-11-22 22:11:22
A palindrome date, time and datetime (: Just realized that on 22-11–22, 22:11:22 I had exactly 212 HN karma points - surely the Universe is trying to say something… Now the question is, would you like to be downvoted to maintain stasis, or try to get to 2112 karma before tomorrow? :) yup, you've hit your peak. it's all downhill from here :-D Oh My Golly, guys - it was the announcement of the Coming of chatGPT! Unix time 1666666666 happened last month, on October 25th 02:57:46 UTC. A closer "round" number will be 1670000000, happening next month on December 2nd 16:53:20 UTC. But for 1700000000 we'll have to wait until next year, November 14th 22:13:20 2023 UTC. 1666666666 was special, though. A beast of a number, no, three beasts of a number. Am I correct that the 32nd prime is 1,453,168,141, and the 33rd prime is 2,300,942,549? I've noticed good times like that getting fewer and farther between. I still regret missing Michael Scott's 05-05-05 party. It only happens once every billion years. It could happen pretty often. Just need to start enough calendars. Surely every 100 years? He was quoting Michael Scott. I had to google "Michael Scott" I'm guessing it's from The Office not the ex-CEO of Apple. I wonder if there was a single person in 1922 that had the same thought. ...or last year, on Nov. 12th. or 11-11-11 11:11:11 or 01-01-01 10:10:10 Interview question: write a program to list them all! > write a program to list them all! Me: Is it OK if it doesn't print until it's done? Interviewer: Uh, sure, why not? Me: while(1){} Me: Finished. This produces the exact desired output of the program you specified. Interviewer: GTFO. while(1) {} is the universal program to do anything. You can then optimise performance later. Interestingly in Haskell the only pure program of type variable “a”
where a means any type at all is the one that never quits: Sounds like a great Code Golf contest. ruby -e 'require"date";a=DateTime.new(0,1,1,0,0,0);(0..4e9).each{|d|b=(a+Rational(d,86400));c=b.strftime("%y%m%d%H%M%S");puts b.strftime("%y-%m-%d %H:%M:%S")if c==c.reverse}' About the most inefficient anyone could make it, but I think it works! Some saves:
`Rational(d,86400)` -> `d/86400r` Get rid of the variable `a` since it is used in only one place. `DateTime.new(0,1,1,0,0,0)` -> `DateTime.new(0,1,1)` also in newer ruby versions you can use numbered parameters to replace d with _1 and remove `|d|` Pretty sure there might be some more which i do not see immediately :) ruby -e 'require"date";(0..4e9).each{b=DateTime.new(0,1,1)+_1/86400r;c=b.strftime("%y%m%d%H%M%S");puts b.strftime("%y-%m-%d %H:%M:%S")if c==c.reverse}' 151 bytes (including the ruby -e, down from 174.) Thanks! `ruby -e 'require"date";0.upto(4e9){b=DateTime.new(0,1,1)+_1/86400r;c=b.strftime"%y%m%d%H%M%S";p b.strftime"%y-%m-%d %H:%M:%S"if c==c.reverse}'` 142? Sorry if I broke anything, on phone. You need to use puts to avoid quotes being added around the output - so I'll give you 145! I'm on my phone too, I'm impressed I even got something working, you've done brilliantly. Edit: DateTime.new(0) seems to work. 141. ~~`b=DateTime.new(0,1,1)+_1/86400r;`->
`b=_1/86400r+DateTime.new 0`~~ oops ruby -rdate -e'b=DateTime.new 0;loop{b+=1/86400r;c=b.strftime"%y%m%d%H%M%S";puts b.strftime"%y-%m-%d %H:%M:%S"if c==c.reverse}' 127. Script never terminates, but it does display all possibilities, so I think it still passes! Edit: 126. ruby -rdate -e'b=DateTime.new 0;loop{b+=1/86400r;puts b.strftime"%y-%m-%d %H:%M:%S"if(c=b.strftime"%y%m%d%H%M%S")==c.reverse}' I think I'm done for the moment, will revisit tomorrow if you can find any further savings! That doesn't work unfortunately, you need the brackets - DateTime has to be on the left. ah, my bad. This should work for 134: `ruby -r date -e '0.upto(4e9){b=DateTime.new(0)+_1/86400r;puts b.strftime"%y-%m-%d %H:%M:%S"if(c=b.strftime"%y%m%d%H%M%S")==c.reverse}'` PowerShell 7, 108 chars Looks like it would be defeated by the dreaded leap second. They're going away. Resolution 4 of the CGPM 2022[1]. They didn't want to deal with having to add a negative leap second, and it looks likely they'd have to if they didn't end them. [1] https://www.bipm.org/documents/20126/64811223/Resolutions-20... I don't think so. It would be only year 2006 (which map to second 60) which could be a problem, and there wasn't a leap year in that year. 2022-11-22 22:11:22.02 happy 22-11-22 everyone, can't wait to wait for 23-11-23 23-11-32 then Damn double leap days, or are we reverse ISO 8601 now? Laughed out loud at this Where I am it's currently Fibonacci day: 11/23 Coming up soon in UTC :)
Which amounts to the same thing: it can do anything - produce any type - but it takes literally forever. myProg: a
myProg = myProg
0..2e9|%{date(date 0).AddSeconds($_)-f 'yy-MM-dd HH:mm:ss'}|?{$_-match'(.)(.)-(.)(.)-(.)(.) \6\5:\4\3:\2\1'}