Dear friends,↵
↵
Today I tried an experimental format: separate videos. So, today I participated in [contest:1868] and recorded a screencast, but, unlike the previous times, I did not immediately record the editorials. Instead several videos are dedicated to them. So here are the links:↵
↵
* https://youtu.be/uuyVZcExbEI — screencast of [contest:1868];↵
* https://youtu.be/OFKF3oGhvmE — editorial (and upsolving!) of [problem:1869A];↵
* https://youtu.be/JoUOqDvKHuo — editorial (and upsolving!) of [problem:1869B];↵
* https://youtu.be/iS3eusWsx3E — editorial of [problem:1869C] (if you're interested in the coding part, you can find it here: https://youtu.be/uuyVZcExbEI?t=938);↵
* https://youtu.be/1Vu2RSQg0D0 — editorial of [problem:1869D1] and [problem:1869D2] (if you're interested in the coding part, you can find it here: https://youtu.be/uuyVZcExbEI?t=2688);↵
* https://youtu.be/Zn2OkKlgaG0 — editorial of [problem:1869E] (if you're interested in the coding part, you can find it here: https://youtu.be/uuyVZcExbEI?t=5204);↵
* https://youtu.be/i4RO3x1fmjA — editorial (and long, long upsolving!) of [problem:1869F].↵
↵
**UPD:** I recorded the upsolving of [problem:1869F] (see the link above). I guess my explanation was quite fine, but in one case I incorrectly calculated the preconditions, which resulted in WA ([submission:223630659]) and, subsequently, a huge mess and pain. It is still quite educational stuff though: the first half of the video is just a normal editorial (but, alas, with a technical mistake which should't screw the flow of the problem though), and the second one can teach you how to seek for bugs in problems like this one (with a big number of cases).↵
↵
Also keep noted that for now the video is low-resolution. It will fix itself in half an hour or so.
↵
Today I tried an experimental format: separate videos. So, today I participated in [contest:1868] and recorded a screencast, but, unlike the previous times, I did not immediately record the editorials. Instead several videos are dedicated to them. So here are the links:↵
↵
* https://youtu.be/uuyVZcExbEI — screencast of [contest:1868];↵
* https://youtu.be/OFKF3oGhvmE — editorial (and upsolving!) of [problem:1869A];↵
* https://youtu.be/JoUOqDvKHuo — editorial (and upsolving!) of [problem:1869B];↵
* https://youtu.be/iS3eusWsx3E — editorial of [problem:1869C] (if you're interested in the coding part, you can find it here: https://youtu.be/uuyVZcExbEI?t=938);↵
* https://youtu.be/1Vu2RSQg0D0 — editorial of [problem:1869D1] and [problem:1869D2] (if you're interested in the coding part, you can find it here: https://youtu.be/uuyVZcExbEI?t=2688);↵
* https://youtu.be/Zn2OkKlgaG0 — editorial of [problem:1869E] (if you're interested in the coding part, you can find it here: https://youtu.be/uuyVZcExbEI?t=5204);↵
* https://youtu.be/i4RO3x1fmjA — editorial (and long, long upsolving!) of [problem:1869F].↵
↵
**UPD:** I recorded the upsolving of [problem:1869F] (see the link above). I guess my explanation was quite fine, but in one case I incorrectly calculated the preconditions, which resulted in WA ([submission:223630659]) and, subsequently, a huge mess and pain. It is still quite educational stuff though: the first half of the video is just a normal editorial (but, alas, with a technical mistake which should't screw the flow of the problem though), and the second one can teach you how to seek for bugs in problems like this one (with a big number of cases).↵
↵
Also keep noted that for now the video is low-resolution. It will fix itself in half an hour or so.
