feat(archive/imo): formalize IMO 2008 Q2 (#6958)
feat(archive/imo): formalize IMO 2008 Q2 (#6958)




Co-authored-by: Manuel Candales <a84d2da95b7aa89282afcf6713eabd47d759bdf5@gmail.com>

leanprover-community/mathlib,leanprover-community/mathlib