You are probably already familiar with the following cheating methods, submitting your solution on alt account, with 4o, and then deep seek, and then o1, and then o3, finding solutions on telegram, finding solutions on youtube, finding solutions on discord, asking your blue rated friend, asking your purple rated friend, asking your orange rated friend, asking your red rated friend, asking your lgm rated friend, play as a team of cyan, play as a team of blue, play as a team of purple, play as a team of orange, play as a team of red, play as a team of lgm, asking some other blue that is not your friend, asking some other purple that is not your friend, asking some other orange that is not your friend, asking some other red that is not your friend, asking some other Lgm that is not your friend, pay an orange to play the contest for you, pay a red to play the contest for you, pay an LGM to play the contest for you, print out katcl and bring it to IOI, print out cp-algorithim and bring it to IOI, print out wikipedia and bring it to IOI, print out OI-wiki and bring it to IOI, print out Adament's blogs and bring it to IOI, print out Elegia's blogs and bring it to IOI, print out the entirety of coderfoces and bring it to IOI, print out the entirety of Atcoder and bring it to IOI, print out the entirety of Shakespeare’s work and bring it to IOI, print out entirety of the human knowledge and bring it to IOI, print out all strings that matches ^[a-z ]+$ and bring it to IOI, bringing phone to IOI, using phone in IOI, using keyboard macros in IOI, using internet connected keyboard in IOI, using a tablet as a keyboard in IOI, using a computer as a keyboard in IOI, using a potato as a keyboard in IOI, participating in IOI when you are not a highschool student, participating in ICPC world finals more than twice, participating in ICPC regionals more than 5 times, participating in world finals when you are already 30, participating in world finals when you are a coach, participating in ICPC with more than 3 people, continue to submit solutions after 5 hours in IOI, continue to submit solutions after 5 hours in ICPC, continue to submit solutions to div1+2 after 3 hours, bringing more than 25 pages of materials to ICPC world finals, bringing 25 pages of font size 3 materials to ICPC world finals, bringing 25 pages of 3840*2160 with 24 bit colour space squares to ICPC world finals, bringing 25 pages of material that reaches the Bekenstein bound in entropy, using your own computer for ICPC, using your own 1000Hz with rapid trigger keyboard in ICPC, using your own 1080p 540Hz monitor in ICPC, using your own problemset in ICPC, modify the test data as a contestant, modify the problem statement as a contestant, modify the interactor as a contestant, modify the model solution as a contestant, modify the test data not as a contestant, finding vulnerabilities on codeforces frontend, finding vulnerabilities on codeforces backend, finding a zero day exploit and using it on codeforces, buying a zero day exploit and use it on codeforces, buy a botnet and ddos codeforces when you are having a rating drop, finding vulnerabilities on LGMs’ computer, finding vulnerabilities on LGMs’ apple phone, finding vulnerabilities on LGM’s android phone, finding a zero day exploit and use it on LGM’s computers, buying a zero day exploit and use it on LGMs’ phones, bribe the problem setters for problems, social engineering the problem setters for the problems, hack the problemsetters for problems, bribe the testers for solutions, social engineering the testers for solutions, hack the testers for solutions, bribe the coordinators for problems, social engineering the coordinators for problems, hack the cooirdnators for problems, bribe mike for solutions, social engineering mike for solutions, hack mike for solutions, ask mike to rejudge your solution until it does not TLE, ask mike to rejudge your solution until your random algorithms pass with the 1e-10 probability, ask mike to rejudge your RE solution until all undefined behaviors are defined like your own C++ standard, ask mike to rejudge your obviously WA solution until the right cosmic ray bit flips the judgment and give you AC, use time machine to ask o727 for a solution, use time machine to read the editorial, use time machine to read the discussion, use time machine to read tourist’s solution, use a time machine to watch umnik’s screencast, do not use a time machine and watch umniks’ screencast, so now

Count the number of ways to cheat, as cheating could be huge, output it modulo 998244853