Submission #3000247

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Source Code Expand

let () = Scanf.scanf "%d %d" @@ fun n m ->
  let a = Array.init m (fun i -> Scanf.scanf " %d %d" (fun x y -> i+1, x, y)) in
  let c = Array.make (n+2) 0 in
  Array.iter (fun (_, s, t) -> c.(s) <- c.(s) + 1; c.(t+1) <- c.(t+1) - 1) a;
  for i = 1 to n do c.(i) <- c.(i) + c.(i-1) done;
  for i = 1 to n do c.(i) <- c.(i-1) + if c.(i) = 1 then 1 else 0 done;
  let b = Array.fold_left (fun ac (i, s, t) -> if c.(t) - c.(s-1) = 0 then i::ac else ac) [] a
    |> List.rev in
  Printf.printf "%d\n" (List.length b);
  List.iter (Printf.printf "%d\n") b

Submission Info

Judge Result