def cswap(swap: int, x_2: int, x_3: int) ->(int, int):
    """
    Conditional constant-time swap.

    Parameters:
        swap (int): 0 or 1. 1 means swap.
        x_2  (int): First int.
        x_3  (int): Second int.

    Returns:
        (int, int): Formatted as (x_2, x_3)
    """
    dummy = swap * (x_2 - x_3)
    x_2 = x_2 - dummy
    x_3 = x_3 + dummy
    return x_2, x_3
