Dear friends,
Today I tried an experimental format: separate videos. So, today I participated in Codeforces Round 896 (Div. 1) 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 Codeforces Round 896 (Div. 1);
- https://youtu.be/OFKF3oGhvmE — editorial (and upsolving!) of 1869A - Make It Zero;
- https://youtu.be/JoUOqDvKHuo — editorial (and upsolving!) of 1869B - 2D Traveling;
- https://youtu.be/iS3eusWsx3E — editorial of 1869C - Fill in the Matrix (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 1869D1 - Candy Party (Easy Version) and 1869D2 - Candy Party (Hard Version) (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 1869E - Travel Plan (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 1869F - Flower-like Pseudotree.
UPD: I recorded the upsolving of 1869F - Flower-like Pseudotree (see the link above). I guess my explanation was quite fine, but in one case I incorrectly calculated the preconditions, which resulted in WA (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. UPDUPD: the high resolution version has been processed and is available on YouTube.