109. Reorder List

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Step 1 / 43

Speed: 1.0x

Phase 1: Find Middle

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Process Step

Starting reorder list algorithm with input [1, 2, 3, 4, 5].

Variables

head[1, 2, 3, 4, 5]

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Example 1:

Input: head = [1,2,3,4]

Output: [1,4,2,3]

Explanation: The linked list is reordered to alternate between the first and last elements.

Example 2:

Input: head = [1,2,3,4,5]

Output: [1,5,2,4,3]

Explanation: The linked list is reordered to alternate between the first and last elements.

Constraints:

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Time Complexity

O(n)

Space Complexity

O(1)

109. Reorder List

Understand Before Coding

Visualize This Problem

Draw Your Approach

Example 1:

Example 2:

Constraints:

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109. Reorder List

Understand Before Coding

Phase 1: Find Middle

Variables

Visualize This Problem

Draw Your Approach

Example 1:

Example 2:

Constraints:

Learn

Topics

Companies

Hint

Use Cases

Phase 1: Find Middle

Variables