def binarySearch(arr, targetVal):

  left = 0

  right = len(arr) - 1

​

  while left <= right:

    mid = (left + right) // 2

​

    if arr[mid] == targetVal:

      return mid

​

    if arr[mid] < targetVal:

      left = mid + 1

    else:

      right = mid - 1

​

  return -1

​

mylist = [1, 3, 5, 7, 9, 11, 13, 15, 17, 19]

x = 11

​

result = binarySearch(mylist, x)

​

if result != -1:

  print("Found at index", result)

else:

  print("Not found")

​