74 lines
1.8 KiB
Python
74 lines
1.8 KiB
Python
# -*- coding: utf-8 -*-
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from collections import deque
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from enum import Enum
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class State(Enum):
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unvisited = 0
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visited = 1
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class Graph(object):
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def bfs(self, source, dest):
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""" Return True if there is a path from source to dest."""
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if source is None:
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return False
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queue = deque()
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queue.append(source)
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source.visit_state = State.visited
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while queue:
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node = queue.popleft()
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print(node)
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if dest is node:
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return True
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for adjacent_node in node.adj_nodes.values():
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if adjacent_node.visit_state == State.unvisited:
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queue.append(adjacent_node)
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adjacent_node.visit_state = State.visited
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return False
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class Person(object):
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def __init__(self, id, name):
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self.id = id
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self.name = name
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self.friend_ids = []
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class LookupService(object):
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def __init__(self):
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self.lookup = {} # key: person_id, value: person_server
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def get_person(self, person_id):
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person_server = self.lookup[person_id]
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return person_server.people[person_id]
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class PersonServer(object):
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def __init__(self):
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self.people = {} # key: person_id, value: person
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def get_people(self, ids):
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results = []
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for id in ids:
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if id in self.people:
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results.append(self.people[id])
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return results
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class UserGraphService(object):
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def __init__(self, person_ids, lookup):
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self.lookup = lookup
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self.person_ids = person_ids
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self.visited_ids = set()
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def bfs(self, source, dest):
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# Use self.visited_ids to track visited nodes
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# Use self.lookup to translate a person_id to a Person
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pass
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