LM1 | Python Fiddle

class izdeliya:
    def __init__(self, num_name):
        self.name = num_name
        #self.numbers = []
        self.bad_numbers = []
        self.bad_parts_list_short = []
        self.next_bad_number = 0
        self.flag = True

def add (self, next_bad_number):
        self.bad_numbers.append(int(next_bad_number))

def add_from_keyboard(self):
        total_num_N = 19
        bad_num_M = 5
        #total_num_N = int(input("Please enter total number of parts: "))
        #bad_num_M = int(input("Please enter total number of BAD parts: "))
        if bad_num_M < total_num_N and bad_num_M != total_num_N:

for x in range (int(bad_num_M)):

next_bad_num = int(input("Please input bad numbers... hit enter when done: "))
                self.add(next_bad_num)
            #print("bad list is ", self.bad_numbers)

else:
                print("total number of parts should be more then total number of BAD parts")

def shorten_list(self, bad_num_M):
            for x in range(int(bad_num_M)):
                if x > 0 and x < bad_num_M - 1 and self.bad_numbers[x] == self.bad_numbers[x - 1] + 1 and self.bad_numbers[x] == self.bad_numbers[x + 1] - 1:

#self.bad_parts_list_short.append("-")
                    while self.flag == True:
                        self.bad_parts_list_short.append("-")
                        self.flag = False

else:
                    #if self.bad_numbers[x] != self.bad_numbers[x + 1] - 1:
                        #self.bad_parts_list_short.append("@")
                        self.bad_parts_list_short.append(self.bad_numbers[x])

#print(self.bad_parts_list_short)
            line = ''
            for num in self.bad_parts_list_short:
                line += (str(num))
            print (line)

run = izdeliya("")
#run.add_from_keyboard()

run.shorten_list(5)
#run.add_brak_from_keyboard(1)
#run.print_list()
#new_game.sum_n()

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