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37 changes: 20 additions & 17 deletions leetcode/301-400/0384.Shuffle-an-Array/README.md
Original file line number Diff line number Diff line change
@@ -1,28 +1,31 @@
# [384.Shuffle an Array][title]

> [!WARNING|style:flat]
> This question is temporarily unanswered if you have good ideas. Welcome to [Create Pull Request PR](https://github.com/kylesliu/awesome-golang-algorithm)

## Description
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.

**Example 1:**

```
Input: a = "11", b = "1"
Output: "100"
```
Implement the `Solution` class:

## 题意
> ...
- `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.

## 题解
**Example 1:**

### 思路1
> ...
Shuffle an Array
```go
```

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]
```

## 结语

Expand Down
45 changes: 43 additions & 2 deletions leetcode/301-400/0384.Shuffle-an-Array/Solution.go
Original file line number Diff line number Diff line change
@@ -1,5 +1,46 @@
package Solution

func Solution(x bool) bool {
return x
import (
"math/rand"
"time"
)

type Shuffle struct {
origin []int
r *rand.Rand
}

func Constructor(nums []int) Shuffle {
return Shuffle{
origin: nums,
r: rand.New(rand.NewSource(time.Now().UnixNano())),
}
}

func (this *Shuffle) Reset() []int {
this.r = rand.New(rand.NewSource(time.Now().UnixNano()))
return this.origin
}

func (this *Shuffle) Shuffle() []int {
n := len(this.origin)
cur := make([]int, len(this.origin))
copy(cur, this.origin)
for i := n - 1; i > 0; i-- {
j := this.r.Intn(i + 1)
cur[i], cur[j] = cur[j], cur[i]
}
return cur
}
func Solution(nums []int, op []string) [][]int {
c := Constructor(nums)
var ret [][]int
for _, name := range op {
if name == "shuffle" {
ret = append(ret, c.Shuffle())
continue
}
ret = append(ret, c.Reset())
}
return ret
}
19 changes: 9 additions & 10 deletions leetcode/301-400/0384.Shuffle-an-Array/Solution_test.go
Original file line number Diff line number Diff line change
Expand Up @@ -10,30 +10,29 @@ func TestSolution(t *testing.T) {
// 测试用例
cases := []struct {
name string
inputs bool
expect bool
inputs []int
op []string
expect [][]int
}{
{"TestCase", true, true},
{"TestCase", true, true},
{"TestCase", false, false},
{"TestCase1", []int{1}, []string{"shuffle", "rest"}, [][]int{{1}, {1}}},
}

// 开始测试
for i, c := range cases {
t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
got := Solution(c.inputs)
got := Solution(c.inputs, c.op)
if !reflect.DeepEqual(got, c.expect) {
t.Fatalf("expected: %v, but got: %v, with inputs: %v",
c.expect, got, c.inputs)
t.Fatalf("expected: %v, but got: %v, with inputs: %v %v",
c.expect, got, c.inputs, c.op)
}
})
}
}

// 压力测试
// 压力测试
func BenchmarkSolution(b *testing.B) {
}

// 使用案列
// 使用案列
func ExampleSolution() {
}
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