Hello codeforces,

as you may know, the famous book "Looking for a challenge?" is quite beloved by our community, given it has really interesting/hard problems and editorials from problem's writer itself.

Recently I got back to my copy, craving to know if I could solve it entirely. On each question statement, the book gives you a URL for that particular question. The problem is, they are outdated. The last time I tried to upload a solution to that URL, at least it gave me another option to it. But now, this is what we see:

After searching through the web (also here), I couldn't find the site that I once visited, and fortunately I found! Here it is: https://szkopul.edu.pl/

Since some of you do not have a copy yet, the value of the book is in each writer's explanation (which I'm not allowed to make it public) of their question and lastly the questions are public to be solved, I took the time to gather the links to those precious (and freaking hard!! ò.ó) questions:

1. Ants
2. Hyperclock
3. Fishes
4. Pilots
5. Skiers
6. Barricades
7. Travel Agency : https://szkopul.edu.pl/problemset/problem/ndbJELRNtKF-32lPk7ew3XCV/site/?key=statement
8. Mushrooms : https://szkopul.edu.pl/problemset/problem/KVIxa_im2wGYJX99NB31p_nC/site/?key=statement
9. Sweets : https://szkopul.edu.pl/problemset/problem/cEMM4bdcKN06uikzs9BRSqkz/site/?key=statement
10. Coding of permutations : https://szkopul.edu.pl/problemset/problem/jd9o4lcV64v_ec432zTSoqh8/site/?key=statement
11. Rooks : https://szkopul.edu.pl/problemset/problem/dIejmvqlAbsoU1hkjNbd4KtF/site/?key=statement
12. Monkeys : https://szkopul.edu.pl/problemset/problem/neqccAalHI0t2ieiHEEgQHzy/site/?key=statement
13. Plotter :
14. Termites : https://szkopul.edu.pl/problemset/problem/Wa4p6tM-ZrLBEsLFQF1ZTAZf/site/?key=statement
15. Window : https://szkopul.edu.pl/problemset/problem/PQLssAMfHL5sXao6JYIZSMQq/site/?key=statement
16. Altars : https://szkopul.edu.pl/problemset/problem/4zZWWzI9tb_9FGiIbDgtFPUP/site/?key=statement
17. Axes of Symmetry : https://szkopul.edu.pl/problemset/problem/ETArorvqQVqRUJRa4kx02f8D/site/?key=statement
18. Leonardo Numbers : https://szkopul.edu.pl/problemset/problem/yGC3v6-xidN3ZW6QNlBAFZSU/site/?key=statement
19. Ritual :
20. Questions : https://szkopul.edu.pl/problemset/problem/Xbp5u_lCVviSoMvFVgYHz0gT/site/?key=statement
21. Chocolate : https://szkopul.edu.pl/problemset/problem/PJCf09u_Xp0wg95P-mGX3gtx/site/?key=statement
22. Fibonacci sums : https://szkopul.edu.pl/problemset/problem/98e_K-Vvcg5TnMG4-hXTNsFG/site/?key=statement
23. The search :
24. Hashing :
25. Afternoon tea : https://szkopul.edu.pl/problemset/problem/VbC9pm97qF-UbC1kZLinY4FS/site/?key=statement
26. Kangaroos : https://szkopul.edu.pl/problemset/problem/fWtoXJwTg06b-UddjeFgchFb/site/?key=statement
27. Sums : https://szkopul.edu.pl/problemset/problem/4CirgBfxbj9tIAS2C7DWCCd7/site/?key=statement
28. Superknight : https://szkopul.edu.pl/problemset/problem/a5TLgccUv1fV_VVYCzkYZIeO/site/?key=statement
29. Ice skates : https://szkopul.edu.pl/problemset/problem/EwpbJWZPly_zZ5i4ytg_8fDE/site/?key=statement
30. Termites 2 : https://szkopul.edu.pl/problemset/problem/Wm_52pyH5gyWTdhWJfd_dc3j/site/?key=statement
31. Cave : https://szkopul.edu.pl/problemset/problem/5Z9PRRPP-R90WhmbSY_qHd-1/site/?key=statement
32. Shuffle : https://szkopul.edu.pl/problemset/problem/Hsm0_uXNWotMHqLfp6_jDc0S/site/?key=statement
33. Game of tokens :
34. Straight lines : https://szkopul.edu.pl/problemset/problem/ORLuUwsI4VKHyzusPnWbW90c/site/?key=statement
35. Guilds : https://szkopul.edu.pl/problemset/problem/oTsXNiT3SD45VgVS2zqQWj7F/site/?key=statement
36. Reconstruction of byteland : https://szkopul.edu.pl/problemset/problem/pGW6yPN0P1GMmExqS1SRZfVu/site/?key=statement
37. Army training : https://szkopul.edu.pl/problemset/problem/nXF1qOIv5S88utFPI2V_0gt3/site/?key=statement
38. Riddle : https://szkopul.edu.pl/problemset/problem/W8xspxtNAp3cOxDBA13FA3LK/site/?key=statement
39. Fuel : https://szkopul.edu.pl/problemset/problem/5g0vDW-MvMGHfWQqh56jQKx1/site/?key=statement
40. Ploughing : https://szkopul.edu.pl/problemset/problem/6YiP6JA5U15hY94pLwuHoYPg/site/?key=statement
41. Canoes : https://szkopul.edu.pl/problemset/problem/1ARQAJwDYLzPvU7cE2T5qcQk/site/?key=statement
42. Painter's studio : https://szkopul.edu.pl/problemset/problem/yLYgZJFSxjd-pqbjrUvSCOF7/site/?key=statement
43. Triangles :
44. Triangles 2 : https://szkopul.edu.pl/problemset/problem/tX0rS-7EjatV5bZ8pmijgiHZ/site/?key=statement
45. Circular game : https://szkopul.edu.pl/problemset/problem/X7Ad3z3_4Mg7cdrz2GUUNeC_/site/?key=statement
46. Byteland : https://szkopul.edu.pl/problemset/problem/JXaPu39wQfiZaqlM51zlchez/site/?key=statement
47. Cakes : https://szkopul.edu.pl/problemset/problem/XWoCTR5RfPUYrlXIGPad9u2W/site/?key=statement
48. Building blocks : https://szkopul.edu.pl/problemset/problem/KC7c6nYfAXCbCGszqhIeOGxP/site/?key=statement
49. Matching : https://szkopul.edu.pl/problemset/problem/6b-q_dPI_KRHD3VArapVq7EP/site/?key=statement
50. Party :
51. Dice : https://szkopul.edu.pl/problemset/problem/Xo_ptkltMBz_VOEKGB-2RpzB/site/?key=statement
52. Two parties : https://szkopul.edu.pl/problemset/problem/eC-cABL-jWd4JdZDmfWufeeQ/site/?key=statement
53. Guesswork :

For those eagle eyed readers, some questions I couldn't find there, I'm sorry =(

But fear not! If you have the particular missing link, please leave a comment so we can make it complete. Also, if you found anything wrong on this list, also let me know so I can fix it (It's a pretty long list and I'm tired from working all day).

Cheers!