标签：with amp instant duplicate number perm back cal called
Shuffle a set of numbers without duplicates.
Example:
// Init an array with set 1, 2, and 3.
int[] nums = {1,2,3};
Solution solution = new Solution(nums);
// Shuffle the array [1,2,3] and return its result. Any permutation of [1,2,3] must equally likely to be returned.
solution.shuffle();
// Resets the array back to its original configuration [1,2,3].
solution.reset();
// Returns the random shuffling of array [1,2,3].
solution.shuffle();
class Solution { private int[] arr; private Random rand; public Solution(int[] nums) { this.arr = nums; rand = new Random(); } /** Resets the array to its original configuration and return it. */ public int[] reset() { return arr; } /** Returns a random shuffling of the array. */ public int[] shuffle() { int[] tmpArr = arr.clone(); for (int i = 1; i < tmpArr.length; i++) { // need to add 1 int tmpInx = rand.nextInt(i + 1); swap(i, tmpInx, tmpArr); } return tmpArr; } private void swap(int i, int j, int[] arr) { int num = arr[i]; arr[i] = arr[j]; arr[j] = num; } } /** * Your Solution object will be instantiated and called as such: * Solution obj = new Solution(nums); * int[] param_1 = obj.reset(); * int[] param_2 = obj.shuffle(); */
标签：with amp instant duplicate number perm back cal called
原文地址：https://www.cnblogs.com/xuanlu/p/12181767.html
