ChatGPT passed ABC280D under human coaching

Revision en4, by -14, 2022-12-05 08:32:47

The Problem

You are given an integer $$$K$$$ greater than or equal to $$$2$$$. Find the minimum positive integer $$$N$$$ such that $$$N!$$$ is a multiple of $$$K$$$.

Here, $$$N!$$$ denotes the factorial of $$$N$$$. Under the Constraints of this problem, we can prove that such an $$$N$$$ always exists.

Constraint: $$$2 \leq K \leq 10 ^12$$$

The submission

Here are the interactions. ChatGPT spoke Chinese to me (which I didn't figure out how to configure it), so I'd provide some translations here.

Human: (The problem statement with hint to use long long)

ChatGPT: We can use code to implement the above algorithm.

Commment: ChatGPT wrote a bruteforce algorithm that didn't notice the long long type can hardly store a factorial, which is in my expectation.

Human: This code can not process when the factorials are large. You can enumarate the answer, and when newly add $$$n$$$ to the factorial, the $$$\gcd(K, n)$$$ factor can be eliminated, until $$$K = 1$$$. Try to optimize your code.

ChatGPT: In order to solve the above problems, we can optimize the code to handle the case where the factorial is too large. We can use enumeration to find the smallest positive number N that satisfies the condition, and then offset the divisor of gcd (K, n) in K with the order n of N each time until K is 1.

The implementation is as follows. (Code follows)

Comment: !

History

 
 
 
 
Revisions
 
 
  Rev. Lang. By When Δ Comment
en20 English -14 2022-12-06 12:54:39 6 Tiny change: '12}$\n\n[CodeGPT correc' -> '12}$\n\n[ChatGPT correc'
en19 English -14 2022-12-05 09:58:06 2 Tiny change: 'unexpected strong. H' -> 'unexpectedly strong. H'
en18 English -14 2022-12-05 09:23:57 261
en17 English -14 2022-12-05 08:58:22 0 (published)
en16 English -14 2022-12-05 08:57:35 26
en15 English -14 2022-12-05 08:57:04 2 Tiny change: '68c.png)\n\n' -> '68c.png)\n'
en14 English -14 2022-12-05 08:54:52 9 Tiny change: 't process when the ' -> 't process the case when the '
en13 English -14 2022-12-05 08:54:17 15 Tiny change: 'algorithm.\n\n![ ](/' -> 'algorithm. (Code follows)\n\n![ ](/'
en12 English -14 2022-12-05 08:53:57 4
en11 English -14 2022-12-05 08:53:45 542
en10 English -14 2022-12-05 08:52:19 10 Tiny change: 'd output n — 1 instead ' -> 'd output n-1 instead '
en9 English -14 2022-12-05 08:51:03 265
en8 English -14 2022-12-05 08:43:27 108
en7 English -14 2022-12-05 08:42:22 542
en6 English -14 2022-12-05 08:38:04 455
en5 English -14 2022-12-05 08:34:06 170
en4 English -14 2022-12-05 08:32:47 781
en3 English -14 2022-12-05 08:27:00 78 Tiny change: 'orces.com/d4cc97/2.png)' -> 'orces.com/f49f77/2.png)\n\n'
en2 English -14 2022-12-05 08:25:03 164
en1 English -14 2022-12-05 08:18:58 983 Initial revision (saved to drafts)