can anyone explain the hashing solution of this problem?
thanks in advance :)
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There is 2 parts in hash solution:
1) Largest substring(but not prefix or suffix) equal to prefix. Imagine that we know length of this string. Then we can check if there is a string of this length in O(N).
Let's notice if there is such string of length i + 1 there is string with length i. So we can do binary search to find this is O(n * logn)
2) We iterate over all possible answer's lengthes and check two things
a) This length is less than length in 1 part
b) Prefix of this length equals to suffix of this length(using hashes)
So we get O(n * logn) solution