Hello codeforces,↵
↵
as you may know, the famous book ["Looking for a challenge?"](http://www.lookingforachallengethebook.com/) 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 The problem is, they are outdated.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:↵
↵
↵
↵
For those who don't know polish (Or don't know the magic of google translate), this domain is no longer being properly used to host the questions.↵
↵
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](https://szkopul.edu.pl/problemset/problem/hKLVBaShgwgjH3R0nMREDw8g/site/?key=statement) ↵
1. [Hyperclock](https://szkopul.edu.pl/problemset/problem/-Wvu18KzrxHIevX0iW1QpsMM/site/?key=statement)↵
1. [Fishes](https://szkopul.edu.pl/problemset/problem/LBltOu1dcJLw0bIXb0UlKezb/site/?key=statement) ↵
1. [Pilots](https://szkopul.edu.pl/problemset/problem/lcU5m2RAICwNHsdzydb8JTQw/site/?key=statement) ↵
1. [Skiers](https://szkopul.edu.pl/problemset/problem/l2KMMsZLpA66aGrWu-_QVAZI/site/?key=statement) ↵
1. [Barricades](https://szkopul.edu.pl/problemset/problem/1sX3vqLjiqkpxBNI-sh8UC2m/site/?key=statement)↵
1. [Travel Agency](https://szkopul.edu.pl/problemset/problem/ndbJELRNtKF-32lPk7ew3XCV/site/?key=statement) ↵
1. [Mushrooms](https://szkopul.edu.pl/problemset/problem/KVIxa_im2wGYJX99NB31p_nC/site/?key=statement)↵
1. [Sweets](https://szkopul.edu.pl/problemset/problem/cEMM4bdcKN06uikzs9BRSqkz/site/?key=statement) ↵
1. [Coding of permutations](https://szkopul.edu.pl/problemset/problem/jd9o4lcV64v_ec432zTSoqh8/site/?key=statement) ↵
1. [Rooks](https://szkopul.edu.pl/problemset/problem/dIejmvqlAbsoU1hkjNbd4KtF/site/?key=statement) ↵
1. [Monkeys](https://szkopul.edu.pl/problemset/problem/neqccAalHI0t2ieiHEEgQHzy/site/?key=statement)↵
1. Plotter : _your help comes here_↵
1. [Termites](https://szkopul.edu.pl/problemset/problem/Wa4p6tM-ZrLBEsLFQF1ZTAZf/site/?key=statement) ↵
1. [Window](https://szkopul.edu.pl/problemset/problem/PQLssAMfHL5sXao6JYIZSMQq/site/?key=statement)↵
1. [Altars](https://szkopul.edu.pl/problemset/problem/4zZWWzI9tb_9FGiIbDgtFPUP/site/?key=statement) ↵
1. [Axes of Symmetry](https://szkopul.edu.pl/problemset/problem/ETArorvqQVqRUJRa4kx02f8D/site/?key=statement)↵
1. [Leonardo Numbers](https://szkopul.edu.pl/problemset/problem/yGC3v6-xidN3ZW6QNlBAFZSU/site/?key=statement) ↵
1. Ritual : _your help comes here_↵
1. [Questions](https://szkopul.edu.pl/problemset/problem/Xbp5u_lCVviSoMvFVgYHz0gT/site/?key=statement)↵
1. [Chocolate](https://szkopul.edu.pl/problemset/problem/PJCf09u_Xp0wg95P-mGX3gtx/site/?key=statement) ↵
1. [Fibonacci sums](https://szkopul.edu.pl/problemset/problem/98e_K-Vvcg5TnMG4-hXTNsFG/site/?key=statement) ↵
1. The search : _your help comes here_↵
1. Hashing : _your help comes here_↵
1. [Afternoon tea](https://szkopul.edu.pl/problemset/problem/VbC9pm97qF-UbC1kZLinY4FS/site/?key=statement) ↵
1. [Kangaroos](https://szkopul.edu.pl/problemset/problem/fWtoXJwTg06b-UddjeFgchFb/site/?key=statement) ↵
1. [Sums](https://szkopul.edu.pl/problemset/problem/4CirgBfxbj9tIAS2C7DWCCd7/site/?key=statement) ↵
1. [Superknight](https://szkopul.edu.pl/problemset/problem/a5TLgccUv1fV_VVYCzkYZIeO/site/?key=statement) ↵
1. [Ice skates](https://szkopul.edu.pl/problemset/problem/EwpbJWZPly_zZ5i4ytg_8fDE/site/?key=statement) ↵
1. [Termites 2](https://szkopul.edu.pl/problemset/problem/Wm_52pyH5gyWTdhWJfd_dc3j/site/?key=statement) ↵
1. [Cave](https://szkopul.edu.pl/problemset/problem/5Z9PRRPP-R90WhmbSY_qHd-1/site/?key=statement) ↵
1. [Shuffle](https://szkopul.edu.pl/problemset/problem/Hsm0_uXNWotMHqLfp6_jDc0S/site/?key=statement) ↵
1. Game of tokens : _your help comes here_↵
1. [Straight lines](https://szkopul.edu.pl/problemset/problem/ORLuUwsI4VKHyzusPnWbW90c/site/?key=statement) ↵
1. [Guilds](https://szkopul.edu.pl/problemset/problem/oTsXNiT3SD45VgVS2zqQWj7F/site/?key=statement) ↵
1. [Reconstruction of byteland](https://szkopul.edu.pl/problemset/problem/pGW6yPN0P1GMmExqS1SRZfVu/site/?key=statement) ↵
1. [Army training](https://szkopul.edu.pl/problemset/problem/nXF1qOIv5S88utFPI2V_0gt3/site/?key=statement) ↵
1. [Riddle](https://szkopul.edu.pl/problemset/problem/W8xspxtNAp3cOxDBA13FA3LK/site/?key=statement) ↵
1. [Fuel](https://szkopul.edu.pl/problemset/problem/5g0vDW-MvMGHfWQqh56jQKx1/site/?key=statement) ↵
1. [Ploughing](https://szkopul.edu.pl/problemset/problem/6YiP6JA5U15hY94pLwuHoYPg/site/?key=statement) ↵
1. [Canoes](https://szkopul.edu.pl/problemset/problem/1ARQAJwDYLzPvU7cE2T5qcQk/site/?key=statement) ↵
1. [Painter's studio](https://szkopul.edu.pl/problemset/problem/yLYgZJFSxjd-pqbjrUvSCOF7/site/?key=statement) ↵
1. Triangles : _your help comes here_↵
1. [Triangles 2](https://szkopul.edu.pl/problemset/problem/tX0rS-7EjatV5bZ8pmijgiHZ/site/?key=statement) ↵
1. [Circular game](https://szkopul.edu.pl/problemset/problem/X7Ad3z3_4Mg7cdrz2GUUNeC_/site/?key=statement) ↵
1. [Byteland](https://szkopul.edu.pl/problemset/problem/JXaPu39wQfiZaqlM51zlchez/site/?key=statement) ↵
1. [Cakes](https://szkopul.edu.pl/problemset/problem/XWoCTR5RfPUYrlXIGPad9u2W/site/?key=statement) ↵
1. [Building blocks](https://szkopul.edu.pl/problemset/problem/KC7c6nYfAXCbCGszqhIeOGxP/site/?key=statement) ↵
1. [Matching](https://szkopul.edu.pl/problemset/problem/6b-q_dPI_KRHD3VArapVq7EP/site/?key=statement) ↵
1. Party : _your help comes here_↵
1. [Dice](https://szkopul.edu.pl/problemset/problem/Xo_ptkltMBz_VOEKGB-2RpzB/site/?key=statement) ↵
1. [Two parties](https://szkopul.edu.pl/problemset/problem/eC-cABL-jWd4JdZDmfWufeeQ/site/?key=statement) ↵
1. Guesswork : _your help comes here_↵
↵
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!↵
↵
PS : Thanks to my amazing friend and teacher that loaned me this book and never asked it back (I could give him props, linking his account, but he has like 30 different candidate master accounts, so ... enough of lists ¯\\_(ツ)_/¯).
↵
as you may know, the famous book ["Looking for a challenge?"](http://www.lookingforachallengethebook.com/) 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:↵
↵
↵
↵
For those who don't know polish (Or don't know the magic of google translate), this domain is no longer being properly used to host the questions.↵
↵
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](https://szkopul.edu.pl/problemset/problem/hKLVBaShgwgjH3R0nMREDw8g/site/?key=statement) ↵
1. [Hyperclock](https://szkopul.edu.pl/problemset/problem/-Wvu18KzrxHIevX0iW1QpsMM/site/?key=statement)↵
1. [Fishes](https://szkopul.edu.pl/problemset/problem/LBltOu1dcJLw0bIXb0UlKezb/site/?key=statement) ↵
1. [Pilots](https://szkopul.edu.pl/problemset/problem/lcU5m2RAICwNHsdzydb8JTQw/site/?key=statement) ↵
1. [Skiers](https://szkopul.edu.pl/problemset/problem/l2KMMsZLpA66aGrWu-_QVAZI/site/?key=statement) ↵
1. [Barricades](https://szkopul.edu.pl/problemset/problem/1sX3vqLjiqkpxBNI-sh8UC2m/site/?key=statement)↵
1. [Travel Agency](https://szkopul.edu.pl/problemset/problem/ndbJELRNtKF-32lPk7ew3XCV/site/?key=statement) ↵
1. [Mushrooms](https://szkopul.edu.pl/problemset/problem/KVIxa_im2wGYJX99NB31p_nC/site/?key=statement)↵
1. [Sweets](https://szkopul.edu.pl/problemset/problem/cEMM4bdcKN06uikzs9BRSqkz/site/?key=statement) ↵
1. [Coding of permutations](https://szkopul.edu.pl/problemset/problem/jd9o4lcV64v_ec432zTSoqh8/site/?key=statement) ↵
1. [Rooks](https://szkopul.edu.pl/problemset/problem/dIejmvqlAbsoU1hkjNbd4KtF/site/?key=statement) ↵
1. [Monkeys](https://szkopul.edu.pl/problemset/problem/neqccAalHI0t2ieiHEEgQHzy/site/?key=statement)↵
1. Plotter : _your help comes here_↵
1. [Termites](https://szkopul.edu.pl/problemset/problem/Wa4p6tM-ZrLBEsLFQF1ZTAZf/site/?key=statement) ↵
1. [Window](https://szkopul.edu.pl/problemset/problem/PQLssAMfHL5sXao6JYIZSMQq/site/?key=statement)↵
1. [Altars](https://szkopul.edu.pl/problemset/problem/4zZWWzI9tb_9FGiIbDgtFPUP/site/?key=statement) ↵
1. [Axes of Symmetry](https://szkopul.edu.pl/problemset/problem/ETArorvqQVqRUJRa4kx02f8D/site/?key=statement)↵
1. [Leonardo Numbers](https://szkopul.edu.pl/problemset/problem/yGC3v6-xidN3ZW6QNlBAFZSU/site/?key=statement) ↵
1. Ritual : _your help comes here_↵
1. [Questions](https://szkopul.edu.pl/problemset/problem/Xbp5u_lCVviSoMvFVgYHz0gT/site/?key=statement)↵
1. [Chocolate](https://szkopul.edu.pl/problemset/problem/PJCf09u_Xp0wg95P-mGX3gtx/site/?key=statement) ↵
1. [Fibonacci sums](https://szkopul.edu.pl/problemset/problem/98e_K-Vvcg5TnMG4-hXTNsFG/site/?key=statement) ↵
1. The search : _your help comes here_↵
1. Hashing : _your help comes here_↵
1. [Afternoon tea](https://szkopul.edu.pl/problemset/problem/VbC9pm97qF-UbC1kZLinY4FS/site/?key=statement) ↵
1. [Kangaroos](https://szkopul.edu.pl/problemset/problem/fWtoXJwTg06b-UddjeFgchFb/site/?key=statement) ↵
1. [Sums](https://szkopul.edu.pl/problemset/problem/4CirgBfxbj9tIAS2C7DWCCd7/site/?key=statement) ↵
1. [Superknight](https://szkopul.edu.pl/problemset/problem/a5TLgccUv1fV_VVYCzkYZIeO/site/?key=statement) ↵
1. [Ice skates](https://szkopul.edu.pl/problemset/problem/EwpbJWZPly_zZ5i4ytg_8fDE/site/?key=statement) ↵
1. [Termites 2](https://szkopul.edu.pl/problemset/problem/Wm_52pyH5gyWTdhWJfd_dc3j/site/?key=statement) ↵
1. [Cave](https://szkopul.edu.pl/problemset/problem/5Z9PRRPP-R90WhmbSY_qHd-1/site/?key=statement) ↵
1. [Shuffle](https://szkopul.edu.pl/problemset/problem/Hsm0_uXNWotMHqLfp6_jDc0S/site/?key=statement) ↵
1. Game of tokens : _your help comes here_↵
1. [Straight lines](https://szkopul.edu.pl/problemset/problem/ORLuUwsI4VKHyzusPnWbW90c/site/?key=statement) ↵
1. [Guilds](https://szkopul.edu.pl/problemset/problem/oTsXNiT3SD45VgVS2zqQWj7F/site/?key=statement) ↵
1. [Reconstruction of byteland](https://szkopul.edu.pl/problemset/problem/pGW6yPN0P1GMmExqS1SRZfVu/site/?key=statement) ↵
1. [Army training](https://szkopul.edu.pl/problemset/problem/nXF1qOIv5S88utFPI2V_0gt3/site/?key=statement) ↵
1. [Riddle](https://szkopul.edu.pl/problemset/problem/W8xspxtNAp3cOxDBA13FA3LK/site/?key=statement) ↵
1. [Fuel](https://szkopul.edu.pl/problemset/problem/5g0vDW-MvMGHfWQqh56jQKx1/site/?key=statement) ↵
1. [Ploughing](https://szkopul.edu.pl/problemset/problem/6YiP6JA5U15hY94pLwuHoYPg/site/?key=statement) ↵
1. [Canoes](https://szkopul.edu.pl/problemset/problem/1ARQAJwDYLzPvU7cE2T5qcQk/site/?key=statement) ↵
1. [Painter's studio](https://szkopul.edu.pl/problemset/problem/yLYgZJFSxjd-pqbjrUvSCOF7/site/?key=statement) ↵
1. Triangles : _your help comes here_↵
1. [Triangles 2](https://szkopul.edu.pl/problemset/problem/tX0rS-7EjatV5bZ8pmijgiHZ/site/?key=statement) ↵
1. [Circular game](https://szkopul.edu.pl/problemset/problem/X7Ad3z3_4Mg7cdrz2GUUNeC_/site/?key=statement) ↵
1. [Byteland](https://szkopul.edu.pl/problemset/problem/JXaPu39wQfiZaqlM51zlchez/site/?key=statement) ↵
1. [Cakes](https://szkopul.edu.pl/problemset/problem/XWoCTR5RfPUYrlXIGPad9u2W/site/?key=statement) ↵
1. [Building blocks](https://szkopul.edu.pl/problemset/problem/KC7c6nYfAXCbCGszqhIeOGxP/site/?key=statement) ↵
1. [Matching](https://szkopul.edu.pl/problemset/problem/6b-q_dPI_KRHD3VArapVq7EP/site/?key=statement) ↵
1. Party : _your help comes here_↵
1. [Dice](https://szkopul.edu.pl/problemset/problem/Xo_ptkltMBz_VOEKGB-2RpzB/site/?key=statement) ↵
1. [Two parties](https://szkopul.edu.pl/problemset/problem/eC-cABL-jWd4JdZDmfWufeeQ/site/?key=statement) ↵
1. Guesswork : _your help comes here_↵
↵
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,
↵
Cheers!↵
↵
PS : Thanks to my amazing friend and teacher that loaned me this book and never asked it back (I could give him props, linking his account, but he has like 30 different candidate master accounts, so ... enough of lists ¯\\_(ツ)_/¯).
