69 lines
2.0 KiB
Python
69 lines
2.0 KiB
Python
import sys
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import os
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# filename = sys.argv[1]
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# path = os.path.join(os.getcwd(), filename)
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# path = os.path.join(os.getcwd(), 'test1.arg')
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# file = open(path, 'r').readlines()
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class FSA():
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def __init__(self):
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self.initial_state = '0'
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self.current_letter = None
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self.current_state = self.initial_state
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self.acceptance_state = '0'
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self.alphabet = set()
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self.transition_function = [{'in': '0', 'letter': '0', 'out': '1'},
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{'in': '1', 'letter': '1', 'out': '1'},
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{'in': '1', 'letter': '0', 'out': '0'},
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{'in': '0', 'letter': '1', 'out': '0'}]
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def add_letter_to_alphabet(self, letter):
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self.alphabet.add(letter)
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def add_transition_to_transition_function(self, input_state, output_state, letter):
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obj = {'in': input_state, 'letter': letter, 'out': output_state}
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self.transition_function.append(obj)
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# add letter to alphabet
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def specify_end_state(self, end_state):
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self.end_state = end_state
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def check_text(self, text):
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if text == '':
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return 'YES'
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for letter in text:
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if letter not in self.alphabet:
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return 'NO'
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found_function = None
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for func in self.transition_function:
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if func['in'] == self.current_state and func['letter'] == letter:
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found_function = func
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if not found_function:
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self.current_state = '0'
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else:
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self.current_state = found_function['out']
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# print('Input text:{} output text:{} current state:{}'.format(text, output_text, self.current_state))
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if self.current_state == self.acceptance_state:
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return 'YES'
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return 'NO'
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FSA = FSA()
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FSA.alphabet.add('0')
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FSA.alphabet.add('1')
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# lines = ['10','', '0101']
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for line in sys.stdin:
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line = line.rstrip('\n')
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FSA.current_state = FSA.initial_state
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print(FSA.check_text(line))
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