Imagine three points on a number line: one should be close to the main point, while the other should clearly stand apart. Write a function close_far that takes a, b, and c. Return True if one of b or c differs from a by at most 1, and the other differs from both remaining values by 2 or more; otherwise, return False.

def close_far(a: int, b: int, c: int) -> bool: