grokking-algorithms/chapter6/ex6.2.py
2024-01-11 18:28:03 +00:00

49 lines
1016 B
Python

import logging
from collections import deque
from dataclasses import dataclass
logging.basicConfig(level=logging.DEBUG)
logger = logging.getLogger(__name__)
@dataclass
class Node:
name: str
distance: int
graph = {
"cab": [Node("cat", 1), Node("car", 1)],
"cat": [Node("mat", 0), Node("bat", 0)],
"car": [Node("cat", 0), Node("bar", 0)],
"mat": [Node("bat", 0)],
"bar": [Node("bat", 0)],
"bat": [],
}
visited = []
def bfs():
queue = deque()
queue += graph["cab"]
while queue:
logger.debug(queue)
current_node = queue.popleft()
if current_node.name == "bat":
return current_node.distance
if current_node.name in visited:
continue
visited.append(current_node.name)
next_nodes = graph[current_node.name]
for node in next_nodes:
node.distance = current_node.distance + 1
queue += next_nodes
distance = bfs()
print(f"shortest distance from cab to bat: {distance}")