Package g0301_0400.s0384_shuffle_an_array

Class Solution

  • public class Solution
extends Object
    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.

    • Constructor Detail

      • Solution

        public Solution​(int[] nums)

    • Method Detail

      • reset

        public int[] reset()

      • shuffle

        public int[] shuffle()