回答編集履歴
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answer
CHANGED
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@@ -45,4 +45,25 @@
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45
45
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46
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```
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48
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-
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48
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49
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50
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## 追記
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51
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52
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標準ライブラリのみを使った隣接リスト作成の例
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53
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54
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```python
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edges = [(1, 2), (2, 1), (1, 4), (4, 1), (2, 4), (4, 2),
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(4, 3), (3, 4), (4, 5), (5, 4), (3, 5), (5, 3)]
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adj_list = {}
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from itertools import groupby
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for key, group in groupby(sorted(edges), key=lambda x: x[0]):
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conn_to = [g[1] for g in group] # edge=key が接続しているノード一覧
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adj_list[key] = conn_to
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print(adj_list)
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```
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66
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```
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68
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{1: [2, 4], 2: [1, 4], 3: [4, 5], 4: [1, 2, 3, 5], 5: [3, 4]}
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69
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```
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