linked-lists · Problem 1 of 1
Reverse Linked List
easy
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Google
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Microsoft
Apple
AmazonGoogleMetaMicrosoftAppleGiven the head of a singly linked list represented as an array of values, reverse the list and return the reversed array of values.
reverseList([1, 2, 3, 4, 5]) -> [5, 4, 3, 2, 1]
reverseList([1, 2]) -> [2, 1]
reverseList([]) -> []Your solution
Runs your code and animates it without grading anything. Change the input to see what it does on a case the tests do not cover.
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Tests
4 cases, 1 hidden| call | type | expected | result |
|---|---|---|---|
| reverseList([1,2,3,4,5]) | five elements | [5,4,3,2,1] | — |
| reverseList([1,2]) | two elements | [2,1] | — |
| reverseList([1]) | single element | [1] | — |
| withheld | hidden | withheld | — |
Hidden cases run too — their inputs aren't listed here, so aim for a general solution rather than one fitted to the cases above.
Complexity
- target time
- O(n)
- target space
- O(1) auxiliary pointer manipulation (or O(n) array space)
Iterating through n nodes reversing pointers in-place takes linear time with no additional heap allocations.
Hints
Stuck? Hints open one at a time, each giving a little more away.
3 hints left