27 lines
587 B
Python
27 lines
587 B
Python
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from linked_list import Node, from_list
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def kth_to_last_node(k, node):
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one = node
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two = node
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for _ in range(k - 1):
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if not one:
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return None
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one = one.next
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while one.next:
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one = one.next
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two = two.next
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return two.value
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xs = from_list(["Angel Food", "Bundt", "Cheese", "Devil's Food", "Eccles"])
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result = kth_to_last_node(2, xs)
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print(result)
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assert result == "Devil's Food"
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print("Success!")
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xs = from_list(["Angel Food", "Bundt"])
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result = kth_to_last_node(30, xs)
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print(result)
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assert result is None
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print("Success!")
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