import Mathlib.Tactic
/-!
# International Mathematical Olympiad 2010, Problem 1
Determine all functions f : ℝ → ℝ such that for all x,y ∈ ℝ,
f(⌊x⌋y) = f(x)⌊f(y)⌋.
-/
namespace Imo2010P1
/- determine -/ abbrev solution_set : Set (ℝ → ℝ) := sorry
theorem imo2010_p1 (f : ℝ → ℝ) :
f ∈ solution_set ↔ ∀ x y, f (⌊x⌋ * y) = f x * ⌊f y⌋ := sorry
end Imo2010P1
This problem has a complete formalized solution.
The solution was imported from imo-A-and-N/src/IMO2010/A1/A1.lean.