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();
class Solution:
def __init__(self, nums):
"""
:type nums: List[int]
"""
self.nums = nums
self.backup = nums[:]
self.n = len(nums)
def reset(self):
"""
Resets the array to its original configuration and return it.
:rtype: List[int]
"""
self.nums = self.backup
return self.nums
def shuffle(self):
"""
Returns a random shuffling of the array.
:rtype: List[int]
"""
import random
temp = self.nums
res = []
for _ in range(self.n):
cur = random.randint(0, len(temp)-1)
res.append(temp[cur])
temp = temp[:cur] + temp[cur+1:]
self.nums = res
return self.nums
# random.shuffle(self.array)
# return self.array
# Your Solution object will be instantiated and called as such:
# obj = Solution(nums)
# param_1 = obj.reset()
# param_2 = obj.shuffle()
