
    Write a function to determine if a bus route number has a special mirroring property where it is one less than twice its reverse number, which helps identify complementary routes in the transit system. For example, if route 241 exists, check if it equals one less than twice its reverse (142 * 2 - 1) to establish potential route pairing opportunities.
    

    
def rev(num):
    rev_num = 0
    while num > 0:
        rev_num = rev_num * 10 + num % 10
        num = num // 10
    return rev_num

def check(n):
    """
    Write a function to determine if a bus route number has a special mirroring property where it is one less than twice its reverse number, which helps identify complementary routes in the transit system. For example, if route 241 exists, check if it equals one less than twice its reverse (142 * 2 - 1) to establish potential route pairing opportunities.
    

    """
def rev(num):
    rev_num = 0
    while num > 0:
        rev_num = rev_num * 10 + num % 10
        num = num // 10
    return rev_num

def check(n):
    """
    Write a function to determine if a bus route number has a special mirroring property where it is one less than twice its reverse number, which helps identify complementary routes in the transit system. For example, if route 241 exists, check if it equals one less than twice its reverse (142 * 2 - 1) to establish potential route pairing opportunities.
    

    """
    return 2 * rev(n) == n + 1