题目：

题解：

type Solution struct {
    nums, original []int
}

func Constructor(nums []int) Solution {
    return Solution{nums, append([]int(nil), nums...)}
}

func (s *Solution) Reset() []int {
    copy(s.nums, s.original)
    return s.nums
}

func (s *Solution) Shuffle() []int {
    n := len(s.nums)
    for i := range s.nums {
        j := i + rand.Intn(n-i)
        s.nums[i], s.nums[j] = s.nums[j], s.nums[i]
    }
    return s.nums
}