mirror of
https://github.com/halfrost/LeetCode-Go.git
synced 2025-07-06 09:23:19 +08:00
82 lines
2.2 KiB
Markdown
82 lines
2.2 KiB
Markdown
# [384.Shuffle an Array](https://leetcode.com/problems/shuffle-an-array/)
|
|
|
|
## 题目
|
|
|
|
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
|
|
- -1000000 <= nums[i] <= 1000000
|
|
- All the elements of nums are unique.
|
|
- At most 5 * 10000 calls in total will be made to reset and shuffle.
|
|
|
|
## 题目大意
|
|
|
|
给你一个整数数组 nums ，设计算法来打乱一个没有重复元素的数组。
|
|
|
|
实现 Solution class:
|
|
|
|
- Solution(int[] nums) 使用整数数组 nums 初始化对象
|
|
- int[] reset() 重设数组到它的初始状态并返回
|
|
- int[] shuffle() 返回数组随机打乱后的结果
|
|
|
|
## 解题思路
|
|
|
|
- 使用 rand.Shuffle 进行数组随机打乱
|
|
|
|
## 代码
|
|
|
|
```go
|
|
|
|
package leetcode
|
|
|
|
import "math/rand"
|
|
|
|
type Solution struct {
|
|
nums []int
|
|
}
|
|
|
|
func Constructor(nums []int) Solution {
|
|
return Solution{
|
|
nums: nums,
|
|
}
|
|
}
|
|
|
|
/** Resets the array to its original configuration and return it. */
|
|
func (this *Solution) Reset() []int {
|
|
return this.nums
|
|
}
|
|
|
|
/** Returns a random shuffling of the array. */
|
|
func (this *Solution) Shuffle() []int {
|
|
arr := make([]int, len(this.nums))
|
|
copy(arr, this.nums)
|
|
rand.Shuffle(len(arr), func(i, j int) {
|
|
arr[i], arr[j] = arr[j], arr[i]
|
|
})
|
|
return arr
|
|
}
|
|
``` |