using Test

input = open(read, "input")

unique_slice(arr, i, l) = arr[i-l+1:i] |> unique |> length == l

@testset "solution" begin
    @test [
        findfirst(unique_slice(input, i, k) for i = k:length(input)-k+1) + k - 1 for
        k ∈ (4, 14)
    ] == [1655, 2665]
end