let () =
    let n = Scanf.scanf "%d\n" (fun x -> x) in
    let s = Array.to_list (Array.init n (fun i -> Scanf.scanf "%s " (fun x -> (i+1, x)))) in
    let t = Array.to_list (Array.init n (fun i -> Scanf.scanf "%s " (fun x -> (i+1, x)))) in
    let a = List.fold_left2 (fun a (ib, sb) (ic, sc) -> if sb <> sc then [string_of_int ib; sb; sc] else a) [] s t in 
    List.iter print_endline a