Tutis's blog

Codechef Biteration #2 BIT2C complexity
By Tutis, history, 7 years ago, In English

Can someone explain or prove, why calculating all possible values for every interval doesn't get TLE?

I think it should be $$$O(n!)$$$.

My solution.

Problem link.

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7 years ago, hide # |
 
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There were atmost 10 operators

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7 years ago, hide # |
 
Vote: I like it +8 Vote: I do not like it

Ur complexity isn't $$$O(N!)$$$. Infact if u observe the pattern a bit, you'd find that it's complexity never gets multiplied by factor greater than 4 on increasing N by 1. It's pretty much less than $$$O(4^N)$$$ as well, and it's found out to be roughly O(Catalan Number). For more details, u should check the last part of it's official editorial. Ur solution is the DP solution.

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