32 lines
940 B
Python
32 lines
940 B
Python
from collections import deque
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from cfg import config
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from db_util import get_page_id
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def can_reach(title, connection):
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page = get_page_id(title, connection)
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cursor = connection.cursor()
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cursor.execute("SELECT COUNT(destination) FROM links WHERE destination=%s", (page, ))
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count = cursor.fetchone()[0]
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return count > 0
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def shortest_path(center, title, connection):
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if(not can_reach(title, connection)):
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return []
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cursor = connection.cursor()
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current_page = get_page_id(title, connection)
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center_page = get_page_id(center, connection)
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path = deque()
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while(current_page != center_page):
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path.append(current_title)
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cursor.execute('''SELECT links.source
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FROM links
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LEFT JOIN dijkstra_helper ON links.destination=dijkstra_helper.page
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WHERE links.destination=:page
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ORDER BY dijkstra_helper.value ASC
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LIMIT 1''', {"page": current_page})
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current_title = cursor.fetchone()[0]
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return list(reversed(path))
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