under the examples it clearly states that the years are classified in centuries using 'STRICT' construction instead of popular.
This means 1-100 is 1st century, 2000 is 20th century as it shows in the examples given.

IMHO current constraints makes it 6kyu.
At 7kyu brute-force solutions should be accepted.

Groovy Translation

It says "N is greater than 0."
But actually for (4, 1) the answer must be zero.

You need to test for the case when n is the divisor and 2n+1 is the bound and 2n is the solution. I passed the test using a for loop but I would have failed this test so I got a false positive.

Relational databases assume that the order of rows in the resulting set doesn't matter, BUT in this exercise different rows order leads to unacceptable solution. It looks like we need a specific order clause to solve this misconception

For the test: 5 6 3 1 2 4 5 2 2 9 5 7 8 1 8 4 8 5 9 4 6 8 6 3 2 8 2 5 2 5 1 2 5 9 5 1 8 9 4 9 4 1 2 1 4 7 1 1 5 4 1 6 3 6 7 8 2 5 9 7 5 3 7 1 5 4 4 4 1 2 5 8 8 9 5 8 7 8 2 5 4
Expected: equal to 1245789
I get 123456789, why it is not correct?

One random test Random tests
expected 'Not Balanced' to equal 'Balanced' is not passing. Idk what to do. please someone look into my code.

Function signature in initial solution of Haskell should be: extraPerfect :: Int -> [Int]

Whats the take on using Itertools in rust? it's not part of the rust native library, but a lot of solutions are implementing it to make their solutions more functional. Is it okay to use external crates or should we rely only on the native library?