
    Write a function that determines if an event's unique identifier number is one less than twice its reverse, which is used to generate special event pairing codes in a social networking platform's recommendation system. For example, if an event ID is 36, we check if 36 is one less than twice its reverse (63), making it a valid pairing code if the condition is satisfied.
    

    
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 that determines if an event's unique identifier number is one less than twice its reverse, which is used to generate special event pairing codes in a social networking platform's recommendation system. For example, if an event ID is 36, we check if 36 is one less than twice its reverse (63), making it a valid pairing code if the condition is satisfied.
    

    """
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 that determines if an event's unique identifier number is one less than twice its reverse, which is used to generate special event pairing codes in a social networking platform's recommendation system. For example, if an event ID is 36, we check if 36 is one less than twice its reverse (63), making it a valid pairing code if the condition is satisfied.
    

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