binar

let find (arr: 'a array) (element: 'a) : int =
  let l = 0 in
  let r = Array.length(arr) - 1 in
  let rec bin (left: int) (right: int) : int =
    if left > right then -1
    else
      let middle = (left + right) / 2 in
      let mid_val = arr.(middle) in
      if mid_val = element then middle
      else if element > mid_val
      then
        bin (middle + 1) right
      else
        bin left (middle - 1)
  in bin l r
;;