## Sticky

by Alex on Apr 28, 2015 - 11:48:46 pm UTC
• (3/0)
This is the place to post general comments, such as pressing bugs or broader questions.

• (1/1)
Hey jargon, I trust you because I noticed you are very helpful to people but can you help me. I want to know why I have -13 reputations.
PS. Anyone can answer this question.

• (7/0)
I don't want to come off as standoffish or rude in any way, so please take this as my opinion.

It seems to me like you should be focusing on mastering your programming language before you start taking on programming problems. Once you have an idea how a problem should be solved, the translation to code should be simple. Every issue you have posted thus far seems to center around a misunderstanding regarding Python as a language.

Steven and Felix Halim published a list of 11 exercises to test your knowledge of programming languages. Please try any or all of the following -- each one should take _less than 10 lines_. If you can't for most (>6) of them, spend time reviewing programming before you jump to contest problems.

1. Read a double from STDIN. Echo it with field width 7 and 3 digits after the decimal place

2. Given an integer n (<= 15) print pi to n decimal places

3. Given a date in the form of YYYY/DD/MM, print the day of the week
4. Given m random integers, print them in sorted order

5. Given the valid birthdates of n unique people (MM/DD/YYYY) print them sorted first by ascending birth months, then ascending birth dates, then finally by age

6. Given a list of sorted integers (<= 1,000,000 integers) determine if a value L exists in the list using less than 20 comparisons

7. Generate all possible permutations of the first 10 letters of the alphabet

8. Generate all possible subsets of {0, 1, 2, ..., N-1} for N <= 20

9. Given a string representing a number in base X, convert it to base Y (2 <= X, Y <= 36)

10. Define a special word as an alphabet followed by 2 consecutive digits. Given a string replace all special words with 3 stars "***".
e.g. "line: a70 and z72 will be replaced, aa24 and a872 will not"
becomes

"line: *** and *** will be replaced, aa24 and aa872 will not"
11. Given a valid mathematical expression involving '(', ')', '+', '-', '*', '/' in a single line , evaluate that expression (e.g., 3 + (8 - 7.5) * 10 / 5 - (2 + 5 * 7) should produce -33.0, using standard operator precedence)

[semi abridged from Competitive Programming 3, a fantastic read for those looking to up their game]

One thing I've learned in the past couple months is sometimes, problems are too difficult for people. I've tried and failed problems because they were far too difficult for me at the time, then come back to them later to solve them instantly. I've also asked for help to receive an answer, never having that lightbulb moment that allowed me to do it myself the next time. One problem I'll never forget was Knapsack from HackerRank, just the unbounded knapsack problem. I worked on that for hours, until I finally had that epiphany, and suddenly I could do dynamic programming.

If there's a problem you can't solve, try one of these before posting here:

1. Make test cases. Try your own stuff! On this problem, if you try a test case like

tttttttttttttttttttttttttt

s

you might see why your code is failing.

2. Go solve something else. Read a book or watch TV for a while. Come back to the problem with a fresh mindset. Reread your code explaining not only what it does, but why the program needs it to work

3. Save it for later. Try something easier, and next time, you'll stand a better chance.

The reason your reputation is at -13 is probably because the competitive programming community prides itself (rightfully) on the ability of involved individuals to problem solve, and overcome issues. If you can't problem solve when things aren't an easy AC, asking others for help is against the spirit of the community. Asking should be your absolute-i've-worked-on-this-problem-for-days-tearing-my-hair-out-last resort.

Good luck with all your future endeavors though, and I hope you can solve this problem and many, many more to come!

• (15/0)
You gain 10 reputation for every upvote your comments get and you lose 2 reputation for every downvote your comments get. You also lose 1 reputation for every downvote you give.

• (3/0)
I don't remember this being documented. Nice sleuthing! :)

• (1/0)
Aww, it feels good to be trusted. :P

r3mark hit it on the head. However, please don't be tempted to create accounts for the sole purpose of downvoting (or upvoting). This is known as sockpuppetry, and it's banned on Wikipedia, StackExchange, and here. If we discover sockpuppets, we will take some action.

• (1/1)
Hey Mods, typing "++" without the "s into the problem search box yields

"Fatal error: Call to a member function result() on a non-object in /var/trunk/application/models/Problems_model.php on line 252".

I know that searching for "++" serves no particular purpose for your site, but for security purposes, I just thought I would let you know. I hope this helps, and sorry to bother you (I know you guys are busy),

Max

**Edit:** Also, the "Thank-you" page on your legacy website doesn't link properly; there is no '/legacy' in the URL it links to. Just a heads up and great job with your project!

**Edit 2:** I believe that the above is true for all of the links on the legacy site.

• (2/0)

The legacy site hasn't been maintained for years; it's there primarily as a historical curiosity. :) As such I doubt it will be touched.

• (3/0)
A PHP Error was encountered

Severity: Warning

Message: stream_socket_client(): unable to connect to unix:///var/run/pegjudge/socket (No such file or directory)

Filename: controllers/submissions.php

Line Number: 784

An Error Was Encountered

---------------------------

On submitting Python 3 code to two different problems: usacofeb15b1 ccc96p2

• (1/0)
Same here, submitting in C++ doesn't work either.

• (1/0)
Now fixed

• (2/0)
Is there a particular reason?

• (1/0)
Our web host had scheduled maintenance which resulted in the judge being rebooted. There was a bug in one of the init scripts so the back end didn't start up automatically.

• (1/0)
It would be really great if you guys could include the memory the program has been using on the submission status page.

• (1/0)
I may be misinterpreting your comment, but I'm quite sure we already do what you want. On the general submission status page, it appears on the right hand side. On the detail page (the page you go to after submission), it appears after the time taken.

• (1/1)
@bbi5291 : I had read on Quora that we can view others solution here but i am not able to get how? Say I click on problem 's best submissions , it has links only of problem and submitter's handle ??

• (1/1)
If and only if you answered correctly the problem you will see a button named "view" witch should bring you to the person's code.

Again only if you correctly answered the problem.

• (1/1)
It will be really very helpful if problems are tagged , particularly IOI problems ( i guess none of them have been tagged yet!). Btw thanks for the awesume site (Y) :)

• (1/3)
Sorry everyone, the judge is not going to allow submissions from 5:00 pm EST June 26 to 5:00 pm June 30 because I'm submitting an IOI problem with 5000 test cases (30 seconds each). Sorry for the inconvenience.

• (7/0)
This user's account has been suspended.

• (22/2)
Andrew Li sucks

• (15/1)
Strongly agree

• (12/2)
omg i hate that guy, couldn't agree with you more

• (11/2)
I think that the huge time limits for IOI problems can be really annoying for everybody else. If someone submits a really inefficient algorithm, it can literally take 20 mins for the judge to complete all 100 or so test cases. Maybe you can put something to cut off the judge after 3 TLE's in a row or something like that?

• (4/0)
I was trying to access PEG during the day, but it gave me error messages. However, it suddenly worked right now... Did anyone get the same problem or was it because my computer didn't function properly...

• (3/0)
Host was being incompetent with migrations. Should be fine from now on.