Can anyone help me to solve hidden password (ACM 2003, abridged) problem ? link : https://icpcarchive.ecs.baylor.edu/index.php?option=onlinejudge&page=show_problem&problem=756 spoj link : http://www.spoj.com/problems/MINMOVE/ I found many solutions which use suffix array but I didn't get anyone of them. I know what is suffix array but don't know how to apply it here. I just want method to solve this problem. asked 10 Jun '16, 22:12

I couldn't solve "Hidden Password" nor "MINMOVE" but "BEADS" on SPOJ is also similar and I solved it using suffix arrays. I don't know what's the problem with the Live Archive because no matter what I get RE. With MINMOVE I get TLE, and that may be because it requires some more optimization on suffix arrays. (It's also said to have a O(n) solution in the comments below the problem statement,maybe that's the answer to it.) If you already know how to create a classic suffix array, what I did in BEADS (and which most probably also applies to MINMOVE and Hidden Password) is that instead of initializing the second value in the tuple to be 1 when the second index(which is at 2^k distance from first index for step k) exceeds the length of string, I actually initialized it with the value at index (first_index+(2^k))%N. Hope this helps! answered 17 Jan, 02:57
