18 lines
532 B
Python
18 lines
532 B
Python
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# NOTE: Not the best approach, since we use O(N) space
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# Time: O(N)
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class Solution:
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def swapNodes(self, head: Optional[ListNode], k: int) -> Optional[ListNode]:
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# Figure out length of LL and cache nodes by the index
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length = 0
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cache = {}
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ptr = head
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while ptr != None:
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cache[length] = ptr
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length += 1
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ptr = ptr.next
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cache[k - 1].val, cache[length - k].val = cache[length - k].val, cache[k - 1].val
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return head
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