Generate All Permutations

Problem

Return every permutation of distinct integers in lexicographical order.

Examples

Example 1
Input: [1,2,3]
Output: [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
Example 2
Input: [1,2]
Output: [[1,2],[2,1]]

Input and output use JSON-compatible values. For linked-list and tree questions, arrays represent the node structure as described above. Your code should implement solve(input).

Write your solutionImplement solve(input). Your draft is saved in this browser.
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How to solve Generate All Permutations

Return every permutation of distinct integers in lexicographical order. Choose one remaining number at each recursive level. The reference implementation illustrates this approach; check the example and edge cases.

Time and space complexity

O(n·n!) time and O(n·n!) output space.

Practise and improve

Choose JavaScript, TypeScript or Python, complete the starter code, then select Run Tests. Request a hint when you need guidance, or choose View solution and confirm if you would like to study the reference implementation.