I want to use hash table of key : vector and value : int How can i use that ? **Map<vector< int >,int>** uses extra logn factor which many a times doesn't suite me and gives TLE. I just want to store frequency of a kind of vector.

Any help is appreciated. Thanks.

You are taking vector as a key value. There is whole extra factor of n where n is the size of the vector everytime you do operations with map.

That would be okay to me. Just need to make unordered_map instead of map

Can you give link to the problem?

This is my Submission 77023902 , its easy to understand. Problem : 1225D - Произведения-степени

Hey, I solved this problem recently. Hashing the vector won't make a big difference. Try to come with another approach :)

But if you still want to try, polynomial hashing in Robin Karp might be useful here but it will don't give correct answer in every case.

https://codeforces.com/blog/entry/62393?#comment-606294

You can do it by hashing the vector, but if you do that then the complexity will be $$$O(n^2/log$$$ $$$n)$$$, which is still too slow.