feat: 381.Insert Delete GetRandom O(1) Duplicates allowed

kimi0230 · Feb 7, 2024 · 7c9e27d · 7c9e27d
1 parent fafe00a
commit 7c9e27d
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Showing 2 changed files with 19 additions and 2 deletions.
diff --git a/Leetcode/0381.Insert-Delete-GetRandom-O1-Duplicates-allowed/main.go b/Leetcode/0381.Insert-Delete-GetRandom-O1-Duplicates-allowed/main.go
@@ -1,6 +1,8 @@
 package insertdeletegetrandomo1duplicatesallowed
 
-import "math/rand"
+import (
+	"math/rand"
+)
 
 // 時間複雜 O(1), 空間複雜 O(n)
 type RandomizedCollection struct {
@@ -43,13 +45,15 @@ func (this *RandomizedCollection) Remove(val int) bool {
 		break
 	}
 
-	// 與最後一筆交換
+	// 將最後一筆移到要替換的id
 	this.arr[i] = this.arr[this.size-1]
 	delete(ids, i)
 	// 因為把最後一個元素移到前面了
 	delete(this.set[this.arr[i]], this.size-1)
 
 	if i < this.size-1 {
+		// fmt.Printf("i =%d, this.size =%d\t", i, this.size)
+		// 將最後一個元素的index的map中, 最後一個元素的index改為i
 		this.set[this.arr[i]][i] = struct{}{}
 	}
 	if len(ids) == 0 {

diff --git a/Leetcode/0381.Insert-Delete-GetRandom-O1-Duplicates-allowed/main_test.go b/Leetcode/0381.Insert-Delete-GetRandom-O1-Duplicates-allowed/main_test.go
@@ -1,6 +1,7 @@
 package insertdeletegetrandomo1duplicatesallowed
 
 import (
+	"fmt"
 	"reflect"
 	"testing"
 )
@@ -21,6 +22,17 @@ var tests = []struct {
 			nil, true, false, true, true, 1,
 		},
 	},
+	// {
+	// 	[]string{
+	// 		"RandomizedCollection", "insert", "insert", "insert", "getRandom", "remove", "getRandom",
+	// 	},
+	// 	[]int{
+	// 		0, 1, 1, 2, 0, 1, 0,
+	// 	},
+	// 	[]interface{}{
+	// 		nil, true, false, true, 2, true, false, 2,
+	// 	},
+	// },
 }
 
 func TestInsertdeletegetrandom(t *testing.T) {
@@ -39,6 +51,7 @@ func TestInsertdeletegetrandom(t *testing.T) {
 			case "getRandom":
 				result = append(result, rSet.GetRandom())
 			}
+			fmt.Println(rSet.set)
 		}
 		if !reflect.DeepEqual(result, tt.want) {
 			t.Errorf("got = %v, want = %v", result, tt.want)