Package g0301_0400.s0384_shuffle_an_array

Class Solution

java.lang.Object
g0301_0400.s0384_shuffle_an_array.Solution
public class Solution extends java.lang.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 Summary

    Constructors
    Constructor
    Description
    Solution(int[] nums)
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int[]
    reset()
     
    int[]
    shuffle()
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution(int[] nums)

  • Method Details

    • reset

      public int[] reset()

    • shuffle

      public int[] shuffle()