LeetCode 初级 - Shuffle an Array

Shuffle an Array

打乱一个没有重复元素的数组。

示例:

// 以数字集合 1, 2 和 3 初始化数组。
int[] nums = {1,2,3};
Solution solution = new Solution(nums);

// 打乱数组 [1,2,3] 并返回结果。任何 [1,2,3]的排列返回的概率应该相同。
solution.shuffle();

// 重设数组到它的初始状态[1,2,3]。
solution.reset();

// 随机返回数组[1,2,3]打乱后的结果。
solution.shuffle();

代码

    class Solution {
        private int[] origin;
        public Solution(int[] nums) {
            this.origin = nums;
        }

        /** Resets the array to its original configuration and return it. */
        public int[] reset() {
            return origin;
        }

        /** Returns a random shuffling of the array. */
        public int[] shuffle() {
            Random random = new Random();
            int[] nums = (int[])origin.clone();
            for(int i=0;iint seq = random.nextInt(nums.length);
                int tmp = nums[i];
                nums[i] = nums[seq];
                nums[seq] = tmp;
            }
            return nums;
        }
    }

    /**
     * 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();
     */