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Java-based LeetCode algorithm problem solutions, regularly updated
384\. Shuffle an Array
Medium
Given an integer array `nums`, design an algorithm to randomly shuffle the array. All permutations of the array should be **equally likely** as a result of the shuffling.
Implement the `Solution` class:
* `Solution(int[] nums)` Initializes the object with the integer array `nums`.
* `int[] reset()` Resets the array to its original configuration and returns it.
* `int[] shuffle()` Returns a random shuffling of the array.
**Example 1:**
**Input**
["Solution", "shuffle", "reset", "shuffle"]
[[[1, 2, 3]], [], [], []]
**Output:**
[null, [3, 1, 2], [1, 2, 3], [1, 3, 2]]
**Explanation:**
Solution solution = new Solution([1, 2, 3]);
solution.shuffle(); // Shuffle the array [1,2,3] and return its result.
// Any permutation of [1,2,3] must be equally likely to be returned.
// Example: return [3, 1, 2]
solution.reset(); // Resets the array back to its original configuration [1,2,3]. Return [1, 2, 3]
solution.shuffle(); // Returns the random shuffling of array [1,2,3]. Example: return [1, 3, 2]
**Constraints:**
* `1 <= nums.length <= 200`
* -106 <= nums[i] <= 106
* All the elements of `nums` are **unique**.
* At most 5 * 104
calls **in total** will be made to `reset` and `shuffle`.