68 lines
2.0 KiB
Python
68 lines
2.0 KiB
Python
#!/usr/bin/env python
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# -*- coding: utf-8 -*-
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import re
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import sys
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# Regex pattern for reading atandt format
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atandt_desc_pattern = re.compile(r"^([0-9]+)[ \t]([0-9]+)[ \t](\S+)") #^([0-9]+)\t([0-9]+)\t(\S+)$ regex for tab separated columns
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atandt_accepted_state_pattern = re.compile(r"^[0-9]+$")
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current_state = 0
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accept_states = set()
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state_move = set()
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# function that filters set by starting node and returns all edges that starts in that node
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def filter_set(xs, filtered_value):
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return set(filter(lambda x: x[0] == filtered_value, xs))
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def dfs(graph, start):
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visited = set()
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stack = []
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for el in filter_set(state_move, 0):
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stack.append(el)
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while stack:
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edge = stack.pop()
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#print('Current edge: {edge}'.format(edge = edge))
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#return immediately if cycle is detected
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if edge[0] == edge[2]:
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return [-1]
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if edge[2] in accept_states:
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visited = set()
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if edge not in visited:
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visited.add(edge)
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children = set()
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for val in filter_set(state_move, edge[2]):
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stack.append(val)
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#print('Stack: {stack}'.format(stack = stack))
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#print('Visited: {visited}'.format(visited = visited))
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else:
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return [-2]
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return visited
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#print("Start program")
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# load atand format from stdin
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for line in sys.stdin:
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line = line.replace('\n', '')
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#print(line)
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move = atandt_desc_pattern.match(line)
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succes = atandt_accepted_state_pattern.match(line)
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if move:
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node = str(move.group(3))
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state_move.add((int(move.group(1)), node, int(move.group(2))))
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if succes:
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accept_states.add(int(line))
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#print('Moves: {state_move}'.format(state_move = state_move))
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#print('Accept states: {accept_states}'.format(accept_states = accept_states))
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vis = dfs(state_move, 0)
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#print(vis)
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# if edge start and end node is the same
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if -1 in vis:
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print("TAK")
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# if edge is in visited
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elif -2 in vis:
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print("TAK")
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else:
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print("NIE")
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