izhang's blog

By izhang, history, 4 months ago, In English

If you receive a message similar to this, DO NOT CLICK ON IT! The text says codeforces.com, but the actual url redirects you to a cobeforces.com page (with a b instead of a d). It then asks you to sign in and will most likely steal your password.

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By izhang, 6 months ago, In English

NACTF 2021 is a team cp competition with cash prizes for high school students. The competition will be held on Saturday December 4th from 12:00PM EST to 4:00PM EST. The contest will be 4 hours with 9 algorithmic problems of varying difficulty. These problems will be similar in style to those found on codeforces or USACO. The problems difficulties will range from USACO bronze to easy platinum level and our hardest problems will correspond to codeforces ratings of 2300+.


There will be 3 easy problems with 10 test cases each, 3 medium problems with 15 test cases each, and 3 hard problems with 20 test cases each. You will get 1 point for each correct test case. Note: the sample input given in the problem statement will not be one of the test cases. If multiple teams have the same score, the ranking will be determined based on the time of the last submission. There will be no penalty for incorrect submissions, but a submission will still count for tie-breaking purposes even if it does not increase the score of the team.


Anyone may participate in NACTF, however there are restrictions on eligibility for prizes. In order to receive prizes, all team members must be middle school or high school students.

1st place: $175

2nd place: $100

3nd place: $50

4th place: $25

5th place: $25

If you are interested in participating, check out our website: http://cp.nactf.net/

To register, fill out this google form.

There will be also be a ctf cybersecurity part, so check that out if you're interested: https://ctf.nactf.net/

Join our discord server: https://discord.gg/BkN872352z

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By izhang, history, 9 months ago, In English

I'm writing a private IOI style gym contest on cf and I would like the status page to display the results for each test case. For example, this is what a submission to Central-European Olympiad in Informatics, CEOI 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) looks like.

However, for my gym contest, the status page only displays the results for each subtask:

I have tried looking in the gym and polygon settings, but there doesn't seem to be any setting that addresses this.

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