Permutations II

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Problem

Given an integer array nums that may contain duplicate values, return every **distinct** ordering of its elements. Two orderings are the same if they have the same value at every position. Each permutation must list all elements of nums. The permutations themselves may be returned in any order, but no permutation may appear twice.

Examples

Input: nums = [1,1,2]
Output: [[1,1,2],[1,2,1],[2,1,1]]
The two 1s are interchangeable, so only 3 orderings are distinct.
Input: nums = [1,2,3]
Output: [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
All 6 orderings are distinct.

Constraints

  • 1 <= nums.length <= 8
  • -10 <= nums[i] <= 10

What the interviewer grades

A correct solution is one of five scores. The report also grades problem understanding (did you clarify inputs and edge cases before coding), problem solving, communication while you work, code quality, and testing. See a sample report, or read up on the pattern in the lessons.

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