def verify_sin(sin):
    
    if ( type(sin) != str ):
        return False
    
    sin = sin.replace('-', '')
    
    if ( len(sin) != 9 ):
        return False
    
    sum_even = 0
    sum_odd = 0
    odd_temp = 0
    for index in range(0, len(sin) - 1):
        if ( index % 2 == 0 ):
            sum_even += int(sin[index])
        else:
            odd_temp = int(sin[index]) * 2
            if ( odd_temp >= 10 ):
                sum_odd += int(str(odd_temp)[0]) + int(str(odd_temp)[1])
            else:
                sum_odd += odd_temp
    
    total = sum_even + sum_odd
    total = (total + (10 - total % 10)) - total
    
    return str(total) == sin[-1]