August Long Challenge 2020 was a special one because it was the first long-format CodeChef contest since the new rules against plagiarism were announced. The 10-day programming challenge saw 4,12,028 submissions, with top coders and underdogs aiming for the big score all alike.
Of the significant number of submissions, Division 1 received only 24, 873. With a mere 1100 teams/users with successful submissions, Div 1 lived up to its name of being a tougher playing field in the Long Challenge. However, no matter how steep the climb to the top has been, rns5 of Kim Il-sung University Pyongyang, North Korea continued with his winning streak. Basking in the glory of being the rank one holder, the North Korean student earned himself a rating rise of 141 with this competition. Russian coder endagorion who seems to prefer Long Challenges more than any other CodeChef contests, finished at the second spot, just 0.662 behind the top scorer. With an increased rating of 146, the CodeChefer is only one match away from joining the red band club. Holding the third position strong and firm since his last Long Challenge in April, white2302 missed the second spot by 1.164 points. American coder, atomicenergy, who was last seen in July Lunchtime, finally added a 7-star rating to his name finishing fourth at the August Long Challenge. Microsoft professional from Poland, krismaz, who has been in the top 10 in all his recent appearances, finished fifth in the contest. However, the 7-star coder did see a rating drop of 12, despite a commendable performance.
Division 2 may have had comparatively easier problems but with 3, 87, 155 total submissions, claiming the top spot was not easy. With absolutely no prior CodeChef history whatsoever, Chinese coder, wasa85 bagged the first position with a score of 900. The Hangzhou No.2 High School, Zhejiang student got a rating rise of 225 points at his very first contest programming contest. Last seen on July Lunchtime, Russian student, felixarg finished second with an increased rating of 206, making it to the purple band of coders. On the third spot is another CodeChef debutant, ivgechu from Ukraine who earned a 275 rise in rating with the performance. Another one to jump bands with their performance at the August Long Challenge is American coder raynor30. The New Yorker rose to the purple band club with a rating hike of 194. The fifth position saw something incredibly interesting and highly unusual. We have a 24-way tie for the position with coders from all around the world, including thirteen Indians. With all users scoring 800, it seemed like the fifth position was the fiercest battle at not just the August Long. The real culprit was obviously the tiebreaker problem, Ants(Challenge). A tough problem that most failed to solve, leaving no room for the decimal point differences.
Talking of problems, Smallest KMP received the highest number of submissions in Division 1 with accuracy of 28.67. Ants(Challenge) that caused havoc as the Division 2 tiebreaker was also the least solved problem in Division one with just 32 successful submissions. In Division 2, Chef Wars – Return of the Jedi saw the highest number of successful submissions – 28,768. We got hold of the author of Subsequence Frequency Counting, Temirlan Baibolov who believes that anyone experienced in combinatorics should be able to solve his problem. He seemed satisfied with the number of submissions his problem had received.
“The problem is not hard to solve if you are experienced in combinatorics. I initially had a thought that 40-50% per cent of Div1 should be able to solve it. Real numbers turned out to be really close,” said Baibolov.
August Long Challenge 2020 was no easy competition. While submissions poured in heavily, ACs were hard to come by. Division 1 has been the top coders’ ground, while Division2, as the recent trend has been, saw some new names in the top list once again. This is CodeChef writer Debanjan signing for now and looking forward to your comments and reactions on the freshly concluded Long Challenge.